Sensitive fluorescent probe for Al 3+ , Cr 3+ and Fe 3+ : application in real water samples and logic gate

Sensitive fluorescent probe for Al 3+ , Cr 3+ and Fe 3+ : application in real water samples and logic gate | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Sensitive fluorescent probe for Al 3+ , Cr 3+ and Fe 3+ : application in real water samples and logic gate Ziyun Lin, Yu Shi, Yanxi Song, Jiabao Yan, Hongqi Li, Chengxiao Xie This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5386144/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 11 Jan, 2025 Read the published version in Journal of Fluorescence → Version 1 posted 13 You are reading this latest preprint version Abstract Construction of single probes for simultaneous detection of common trivalent metal ions has attracted much attention due to higher efficiency in analysis and cost. A naphthalimide-based fluorescent probe K1 was synthesized for selective detection of Al 3+ , Cr 3+ and Fe 3+ ions. Fluorescence emission intensity at 534 nm of probe K1 in DMSO/H 2 O (9:1, v/v) was significantly enhanced upon addition of Al 3+ , Cr 3+ and Fe 3+ ions while addition of other metal ions (Li + , Na + , K + , Ag + , Cu 2+ , Fe 2+ , Zn 2+ , Co 2+ , Ni 2+ , Mn 2+ , Sr 2+ , Hg 2+ , Ca 2+ , Mg 2+ , Ce 3+ , Bi 3+ and Au 3+ ) did not bring about substantial change in fluorescence emission. The calculated detection limits were 0.32 µM, 0.81 µM, and 0.27 µM for Al 3+ , Cr 3+ , and Fe 3+ , respectively. Probe K1 displayed strong anti-interference ability, a large Stokes shift, rapid response, and applicability in a wide pH range for the simultaneous detection of Al 3+ , Cr 3+ and Fe 3+ in real water samples. Job's plot test showed that the stoichiometric ratio of the complexes formed between probe K1 and the trivalent metal ions was 1:1. The reversible application of probe K1 was realized by addition of Na 2 EDTA. A molecular logic gate was built based on the input-output information. This approach may provide a basis for highly selective and sensitive detection of common trivalent cations and for design of memory devices. Fluorescent probe Trivalent cation Naphthalimide Logic gate Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Introduction As widely used metal ions, trivalent metal ions, especially Al 3+ , Cr 3+ and Fe 3+ are closely related to human health. Aluminium is one of the most abundant elements on earth and is widely used in engineering, automotive industry, batteries, water purification and other fields. However, Al 3+ is not an essential trace element and excessive intake can cause adverse effects on the haematopoietic system, the immune system, the liver and the kidneys, as well as a series of diseases, such as Parkinson's syndrome and Alzheimer's disease [ 1 , 2 ]. Chromium is one of the essential trace elements for human growth and development, but a high concentration of Cr 3+ will affect the activity of enzymes in the body, destroy the cellular structure, lead to a loss of balance in redox, impede the normal work of the body's antioxidant system, damage the skin, liver, intestines, respiratory system, etc., leading to skin erythema, ulcers, oedema, etc., and cause swelling of the nasal mucous membranes, headache, shortness of breath, loss of olfactory sensation, nasal haemorrhage and other hazards [ 3 ]. Iron is the most abundant of the essential trace elements in the human body and plays a very important role in physiological activities such as transport and storage of oxygen, synthesis of pigments and some metalloenzymes in cells, and enhancement of immune function [ 4 ]. Iron deficiency can lead to dysfunction of several systemic organs such as the haematological system, digestive system, circulatory system and nervous system. Excess iron can also cause serious conditions such as tissue damage, liver and spleen dysfunction, tumors and even death [ 5 – 7 ]. Therefore, it is of great importance to establish effective methods for the detection of the above three metal ions. Currently, X-ray photoelectron spectroscopy (XPS), atomic spectrometry, mass spectrometry, and inductively coupled plasma emission spectroscopy (ICP) are commonly used in the chemical and biological fields to detect metal ions [ 8 – 10 ]. These methods are efficient, rapid and accurate, but they are difficult and limited in detection of trivalent metal ions because of the need for large-scale equipment and complex operation. Fluorescent molecular probes are widely used for the detection of various metal ions because of their high sensitivity, good selectivity, short response time and direct observation. At present, some fluorescent probes have been reported for simultaneous detection of Al 3+ , Cr 3+ and Fe 3+ [ 11 – 22 ]. A large part of these probes suffer from low selectivity due to the interference from competitive metal cations including divalent ions Zn 2+ [ 13 ], Pd 2+ [ 15 ], Hg 2+ [ 20 , 22 ], Cu 2+ [ 23 , 24 ], other trivalent cations Ga 3+ , In 3+ , Tl 3+ and Gd 3+ [ 16 ], Ga 3+ and In 3+ [ 21 ], Ga 3+ [ 25 ], Ga 3+ , In 3+ and As 3+ [ 26 ], La 3+ and Ce 3+ [ 27 ], Ru 3+ and Au 3+ [ 28 ], Ga 3+ , In 3+ and Cu 2+ [ 29 ], and anions PO 4 3– [ 30 ], MnO 4 – and Cr 2 O 7 2– [ 31 ], PO 4 3– , MnO 4 – , Cr 2 O 7 2– and C 2 O 4 2– [ 32 ]. Owing to the paramagnetic nature of Fe 3+ and Cr 3+ , many fluorescent probes for common trivalent metal ions show response mode of fluorescence quenching [ 23 , 26 , 33 – 36 ], which seriously affects the sensitivity of detection. Moreover, the weak coordination ability of Al 3+ ions and robust hydration of Al 3+ ions in water also brings difficulty and challenge in development of fluorescent probes with outstanding selectivity and sensitivity for simultaneous and fast detection of Fe 3+ , Cr 3+ and Al 3+ ions in aqueous media. Considering that naphthalimide fluorophore has been proved effective platform for construction of fluorogenic chemosensors to detect Fe 3+ , Cr 3+ and Al 3+ ions [ 37 – 41 ], and trivalent metal ions prefer a multi-dentate ligand to mono- or bi-dentate ligand, we designed and synthesized a new probe K1 by introducing N-hydroxyethyl piperazine and hydroxyethyl ethylenediamine groups into the 1,8-naphthalic anhydride skeleton to endow the system with multi-dentate coordination sites and improved solubility. The developed probe displayed high stability, good water-solubility, and excellent specificity and sensitivity towards trivalent Fe 3+ , Cr 3+ and Al 3+ ions in aqueous solution. Herein we report the synthesis, characterization, sensing performance, and application in real water samples and logic gate of the new fluorogenic probe. Experimental Materials and Instruments The chemicals, reagents and solvents were of analytical purity and were purchased from commercial channels, putting into use without further purification unless otherwise stated. Melting points were obtained on an AWRS-2A capillary melting instrument with the quoted temperatures being uncorrected. 1 H nuclear magnetic resonance ( 1 H NMR) and 13 C NMR spectra were recorded on a Bruker AM 400 spectrometer. Dimethyl sulfoxide-d 6 (DMSO-d 6 ) was used as solvent and chemical shift recorded was internally referenced to tetramethylsilane (Me 4 Si). Infrared (IR) spectra were determined on a Thermo Fisher Scientific Nicolet 380 Fourier Transform (FT) IR spectrophotometer. Mass spectra were recorded on an Agilent 6000 LC–MS instrument using electronspray ionization (ESI) mode. Fluorescence and ultraviolet-visible (UV-vis) spectra were obtained on a Hitachi F-4500 spectrofluorometer and a JASCO V530 spectrometer, respectively. Synthesis of Compound 1 To a flask was added 4-bromo-1,8-naphthalic anhydride (1.000 g, 3.61 mmol), N-hydroxyethyl piperazine (0.940 g, 7.22 mmol), and ethylene glycol monomethyl ether (8 mL). The mixture was refluxed at 130°C overnight. After reaction, the reaction solution was slowly added dropwise to 50 mL of water, filtered and washed with water to obtain compound 1 as a yellow solid (0.880 g, 74.7%). Mp: 116–117°C. 1 H NMR (400 MHz, DMSO-d 6 ): δ 8.47 (d, J = 7.7 Hz, 2H), 8.39 (d, J = 8.1 Hz, 1H), 7.82 (t, J = 7.9 Hz, 1H), 7.33 (d, J = 8.2 Hz, 1H), 4.50 (s, 1H), 3.58 (t, J = 6.3 Hz, 2H), 3.30 (s, 4H), 2.75 (t, J = 4.7 Hz, 4H), 2.54 (t, J = 6.2 Hz, 2H). Synthesis of Probe K1 Anhydrous ethanol (30 mL) was added to a flask containing compound 1 (1.648 g, 5.05 mmol) and hydroxyethyl ethylenediamine (0.531 g, 5.10 mmol). The mixture was refluxed at 80°C for 6 h. The progress of the reaction was monitored by thin layer chromatography (TLC) and upon completion of the reaction, the filtrate was withdrawn, the filtrate was spun dry, recrystallized from ether and withdrawn to give probe K1 as a yellow solid (1.39 g, 67.1%). Mp: 122–123°C. 1 H NMR (400 MHz, DMSO-d 6 ): δ 8.45–8.32 (m, 3H), 7.77 (t, J = 7.9 Hz, 1H), 7.28 (d, J = 8.1 Hz, 1H), 4.52 (s, 2H), 4.10 (t, J = 6.9 Hz, 2H), 3.59 (t, J = 6.2 Hz, 2H), 3.42 (t, J = 5.7 Hz, 2H), 3.21 (t, J = 4.7 Hz, 3H), 2.79 (t, J = 6.9 Hz, 2H), 2.74 (t, J = 4.7 Hz, 4H), 2.62 (t, J = 5.7 Hz, 2H), 2.54 (s, 2H), 1.94 (s, 1H). 13 C NMR (101 MHz, DMSO-d 6 ): δ 163.93, 163.39, 155.89, 132.42, 130.84, 130.66, 129.36, 126.15, 125.50, 122.82, 115.76, 115.14, 60.79, 60.69, 59.06, 53.61, 53.07, 51.87, 47.30. HR-MS: m/z 413.2172 (M + + H); calcd. for C 22 H 29 N 4 O 4 413.2189. Measurement of Absorption and Fluorescence Spectra Probe K1 was dissolved in N,N-dimethylformamide (DMF) to prepare a stock solution (20 µM) for spectral measurement. Before fluorescence emission and UV-vis absorption spectral tests, the salts including LiNO 3 , NaNO 3 , KNO 3 , AgNO 3 , Cu(NO 3 ) 2 ·3H 2 O, FeSO 4 ·7H 2 O, Zn(NO 3 ) 2 ·6H 2 O, Co(NO 3 ) 2 ·6H 2 O, NiCl 2 ·6H 2 O, Mn(NO 3 ) 2 ·4H 2 O, SrCl 2 ·6H 2 O, Hg(OAc) 2 , CaCl 2 , MgCl 2 , Al(NO 3 ) 3 ·9H 2 O, CrCl 3 ·6H 2 O, Fe(NO 3 ) 3 ·9H 2 O, CeCl 3 , BiCl 3 and K(AuCl 4 ) were dissolved in deionized water. The concentration of these stock solutions was 20 µM. For the fluorescence spectral test, the excitation wavelength was 406 nm, and the excitation and emission slits were both 10.0 nm. Results and Discussion Synthesis of Probe K1 The synthetic route to the new probe K1 is showed in Scheme 1 . Compound 1 was synthesized and characterized following the methodology of literature [ 42 ]. Nucleophilic substitution reaction of the two compounds in ethylene glycol monomethyl ether gave compound 1 in 74% yield. Nucleophilic addition-elimination reaction of compound 1 with hydroxyethyl ethylenediamine in anhydrous ethanol gave the target probe K1 in 67% yield. The chemical structure of K1 was fully characterized by FT-IR (Fig. S1 ), 1 H NMR (Fig. S2), 13 C NMR (Fig. S3), and mass spectrometry (Fig. S4). In the IR spectrum, the peak at 3296 cm ‒1 is attributed to the O‒H and N‒H stretching vibration. The band located at 3083 cm ‒1 is ascribed to the stretching vibration of the C‒H bond on the phenyl rings. The peak at 2822 cm ‒1 is originated from C‒H bond stretching vibrations and the band at 1641 cm ‒1 is attributed to the C = O stretching vibration. The peaks at 1588 cm ‒1 and 1513 cm ‒1 are caused by C = C bond stretching vibration. The peaks at 1348 cm ‒1 and 1232 cm ‒1 are originated from C‒N bond stretching vibration. The bands at 1132 cm ‒1 and 1037 cm ‒1 are attributed to the C‒O stretching vibration. The peaks at 780 cm ‒1 and 758 cm ‒1 are caused by C‒H bond bending vibration. In the proton NMR spectrum, the signals at 8.45–8.32, 7.77 and 7.28 ppm are ascribed to the protons on the naphthylimide ring. The chemical shifts of the methylene protons appeared at 4.52, 4.10, 3.59, 3.42, 2.79 and 2.62 ppm. The signal of the active proton on OH group appeared at 1.94 ppm (singlet). All the spectral data were consistent with the structure of K1 . Fluorescence Spectra of Probe K1 in Different Media Fluorescence spectra of probe K1 (20 µM) in different solvents including DMF, DMSO, ethanol (EtOH), water (H 2 O), and acetonitrile (MeCN) were determined (Fig. S5), from which it was seen that while probe K1 showed the strongest fluorescent emission in deionised water, the difference in fluorescence emission intensity of probe K1 in different organic solvents was not significant. Subsequent tests showed that probe K1 failed to show high selectivity for metal ions in H 2 O and EtOH. However, probe K1 was able to specifically recognize trivalent metal ions in DMSO, so the latter was chosen as the organic medium for sensing performance test. In the course of investigating the suitability of probe K1 in aqueous solution, it was found that probe K1 exhibited steady fluorescence emission and good selectivity for trivalent metal ions in DMSO/H 2 O (9:1, v/v), which was used as the medium in the following detection tests. Fluorogenic Response of Probe K1 to Al, Cr and Fe Changes in UV-vis absorption and fluorescence emission spectra of probe K1 (20 µM) in DMSO/H 2 O (9:1) upon addition of 20 µM of different metal ions (Li + , Na + , K + , Ag + , Cu 2+ , Fe 2+ , Zn 2+ , Co 2+ , Ni 2+ , Mn 2+ , Sr 2+ , Hg 2+ , Ca 2+ , Mg 2+ , Al 3+ , Cr 3+ , Fe 3+ , Ce 3+ , Bi 3+ and Au 3+ ) were recorded as showed in Fig. 1. Addition of common trivalent Fe 3+ , Cr 3+ and Al 3+ ions caused distinct blue shift in the absorption spectrum of probe K1 solution. While addition of other metal ions failed to bring about substantial change in the absorption spectrum of probe K1 . Addition of Fe 3+ , Cr 3+ and Al 3+ ions into probe K1 solution resulted in significant enhancement of fluorescence emission intensity in DMSO/H 2 O (9:1), while addition of other metal ions including trivalent Ce 3+ , Bi 3+ and Au 3+ did not cause significant change in the fluorescence emission. The fluorescence quantum yields of probe K1 and its complexes with Fe 3+ , Cr 3+ and Al 3+ were measured by using Rhodamine B ( Φ = 0.69) as the standard [ 43 ]. Probe K1 exhibited a low quantum yield of 0.005. The complexes formed between probe K1 and Al 3+ , Cr 3+ , Fe 3+ , respectively displayed a Φ value of 0.49, 0.33, 0.63, respectively. Therefore, K1 can be used as a fluorescence turn-on probe for the detection of Al 3+ , Cr 3+ and Fe 3+ in an aqueous solution. Figure 1 UV-vis absorption (a), fluorescence emission (excitation wavelength 406 nm) spectra (b), and color changes under 365 nm UV lamp irradiation (c) of probe K1 (20 µM) in DMSO/H 2 O (9:1) before and after addition of 20 µM of different metal ions (Li + , Na + , K + , Ag + , Cu 2+ , Fe 2+ , Zn 2+ , Co 2+ , Ni 2+ , Mn 2+ , Sr 2+ , Hg 2+ , Ca 2+ , Mg 2+ , Al 3+ , Cr 3+ , Fe 3+ , Ce 3+ , Bi 3+ and Au 3+ ) In order to investigate the interference of other metal ions on the selective detection of Al 3+ by probe K1 , the changes in fluorescence intensity at 534 nm of probe K1 (20 µM) after addition of Al 3+ (20 µM) and/or other competitive metal ions (20 µM) were obtained (Fig. S6). It could be seen that Cr 3+ and Fe 3+ interfered with the selective detection of Al 3+ because K1 was able to detect these three ions at the same time, and the addition of Ce 3+ , Bi 3+ and Au 3+ also brought about interference, but the fluorescence detection of Al 3+ could still be achieved. Similarly, the changes in fluorescence intensity at 534 nm of probe K1 (20 µM) after addition of Cr 3+ or Fe 3+ (20 µM) and/or other competing metal ions (20 µM) were also recorded as showed in Fig. S7 and Fig. S8, respectively. The results indicated that addition of competitive metal ions including Mn 2+ , Al 3+ , Fe 3+ , Ce 3+ , Bi 3+ and Au 3+ caused interference to the selective of Cr 3+ . While the existence of competitive metal ions including Al 3+ , Cr 3+ , Ce 3+ , Bi 3+ and Au 3+ interfered with the selective detection of Fe 3+ by probe K1 . Titration of probe K1 with Al 3+ concentration was carried out. Fluorescence emission spectra of probe K1 (20 µM) in DMSO/H 2 O (9:1) were measured after addition of different concentrations of Al 3+ (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 µM). Variation of fluorescence intensity at 534 nm of probe K1 (20 µM) in DMSO/H 2 O (9:1) with Al 3+ concentration (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 µM) was obtained (Fig. S9). The intensity of the fluorescence emission band was plotted linearly against the concentration of Al 3+ added to probe K1 , which showed a gradual increase in fluorescence intensity as the concentration of added Al 3+ increased from 2 µM to 20 µM. The linear fitting equation was Y = 357242.2X – 16584500.0 with R 2 of 0.992. The limit of detection (LOD) of probe K1 for Al 3+ was calculated to be 0.32 µM according to the equation L = 3S/K, where L is the limit of detection, S denotes the standard deviation of the fluorescence intensity of the blank and K represents the slope of the calibration curve. Similarly, titration of probe K1 with Cr 3+ or Fe 3+ concentration was carried out. Fluorescence emission spectra of probe K1 (20 µM) in DMSO/H 2 O (9:1) after addition of different concentrations of Cr 3+ (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 µM) were determined and variation of fluorescence intensity at 534 nm of probe K1 (20 µM) in DMSO/H 2 O (9:1) with Cr 3+ concentration (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 µM) was obtained (Fig. S10). The intensity of the fluorescence emission at 534 nm increased as the concentration of added Cr 3+ increased from 2 µM to 20 µM. The linear fitting equation was Y = 140582.3X – 6694646.6 with R 2 = 0.994. The detection limit of probe K1 was calculated to be 0.81 µM for Cr 3+ . Fluorescence emission spectra of probe K1 (20 µM) in DMSO/H 2 O (9:1) after addition of different concentrations of Fe 3+ (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 µM) were determined and variation of fluorescence intensity at 534 nm of probe K1 (20 µM) in DMSO/H 2 O (9:1) with Fe 3+ concentration (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 µM) was showed in Fig. S11, from which it could be seen that the fluorescence intensity at 534 nm gradually increased as the concentration of added Fe 3+ increased from 2 µM to 20 µM. The linear fitting equation was obtained as Y = 421080.0X – 12050800.0 with R 2 = 0.982 and the detection limit of probe K1 was calculated to be 0.27 µM for Fe 3+ . To investigate the response time of probe K1 to the trivalent cations, variation of fluorescence intensity of probe K1 (20 µM) at 534 nm with time after addition of Al 3+ (20 µM) in DMSO/H 2 O (9:1) was obtained (Fig. S12). It was seen that the fluorescence intensity increased sharply within the first 15 s upon Al 3+ addition and then increased gradually and very slowly, indicating that probe K1 was sensitive to Al 3+ and suitable for the rapid detection of Al 3+ . Similarly, the change of fluorescence intensity of probe K1 (20 µM) at 534 nm with time after addition of Cr 3+ (20 µM) was recorded in Fig. 2 , from which it was found that the fluorescence intensity increased sharply within the first 25 s after Cr 3+ was added, and then remained essentially stabilized for 125 s, indicating that probe K1 was sensitive to Cr 3+ and qualified for the rapid detection of Cr 3+ . Changes of fluorescence intensity of probe K1 (20 µM) at 534 nm with time after addition of Fe 3+ (20 µM) was recorded in Fig. S13, from which it was found that the fluorescence intensity increased sharply within the first 15 s after Fe 3+ was added, and then declined to gradually stabilize at 25 s, indicating that probe K1 was sensitive to Fe 3+ and was a good candidate for rapid detection of Fe 3+ . Therefore, probe K1 probe displayed high sensitivity to the common trivalent cations Al 3+ , Cr 3+ and Fe 3+ and could be used for the rapid detection of these ions. In order to investigate the sensing mechanism of probe K1 for the detection of Al 3+ , Cr 3+ and Fe 3+ , and to understand the coordination pattern between probe K1 and Al 3+ , Cr 3+ and Fe 3+ , Job's plots were drawn. Changes of the fluorescence intensity at 534 nm with the molar fraction of Fe 3+ in probe K1 solution containing Fe 3+ in DMSO/H 2 O (9:1) were determined, as showed in Fig. 3 . It could be seen that probe K1 formed 1:1 stoichiometric complex with Fe 3+ . Similarly, changes of the fluorescence intensity at 534 nm with the molar fraction of Al 3 + or Cr 3+ in probe K1 solution containing Al 3 + or Cr 3+ in DMSO/H 2 O (9:1) were obtained (Fig. S14 and Fig. S15, respectively), which demonstrated that the stoichiometric ratio of probe K1 -Al 3+ and probe K1 -Cr 3+ complex was 1:1. In order to investigate the effect of pH on the detection of Al 3+ , Cr 3+ and Fe 3+ by probe K1 , the test solution of probe K1 (20 µM) was configured in DMSO/H 2 O (9:1) at pH 1–14, respectively. Fluorescence intensities at 534 nmm of probe K1 (20 µM) and the mixture of probe K1 with equivalent Al 3+ (20 µM) at different pH conditions (pH 1–14) were tested as showed in Fig. 4 . The results revealed that addition of equivalent Al 3 + to probe K1 remarkably enhanced the fluorescence emission intensity of the weakly fluorescent probe K1 at pH 4–10. Similarly, fluorescence intensities at 534 nmm of probe K1 (20 µM) and the mixture of probe K1 with equivalent Cr 3 + or Fe 3+ (20 µM) at different pH conditions (pH 1–14) were obtained (Fig. S16 and Fig. S17, respectively), which also indicated that addition of equivalent Cr 3 + and Fe 3 + to probe K1 could enhance the fluorescence intensity of probe K1 at pH 4–10. Therefore, probe K1 could be used to detect Al 3+ , Cr 3+ and Fe 3+ in DMSO/H 2 O (9:1) at a wide range of pH 4–10. Study on the Sensing Mechanism of Probe K1 Sensing mechanism of probe K1 towards trivalent Al 3+ , Cr 3+ and Fe 3+ ions was proposed as showed in Fig. 5 . The hydroxyethylpiperazine moiety in probe K1 , which acted as a tridentate ligand, could provide multiple coordination sites for complexing with trivalent metal ions in 1:1 stoichiometry, as identified by the above-mensioned Job’s plot study. The proposed mechanism was verified by comparison of the proton NMR spectrum of probe K1 with those of the products of the reaction between probe K1 and Al 3+ , Cr 3+ and Fe 3+ ions (Fig. S18). The broad signal at 1.94 ppm attributed to the hydroxyl proton in probe K1 disappeared after addition of trivalent Al 3+ , Cr 3+ and Fe 3+ ions, which implied the complexation between probe K1 and Al 3+ , Cr 3+ and Fe 3+ ions. The complexation hindered the intramolecular charge transfer (ICT) process, thereby enhancing the fluorescence intensity. In addition, HR-MS of the product of the reaction between probe K1 and Al 3+ was measured (Fig. S19) to further support the above sensing mechanism. A characteristic peak appeared at m/z 396.9 (less than m/z 412.2 corresponding to the molecular weight of K1 ) was observed. It might be formed by deoxygenation of K1 due to the complexation with Al 3+ , which weakened the C–O bonding. Next, the reversibility of the sensing process was investigated. The complexes formed between probe K1 and trivalent Al 3+ , Cr 3+ and Fe 3+ ions were titrated with ethylenediaminetetraacetic acid disodium salt (Na 2 EDTA). Fluorescence spectra of probe K1 upon addition of trivalent Al 3+ , Cr 3+ and Fe 3+ and subsequently Na 2 EDTA were determined, respectively (Fig. S20). The fluorescence emission intensity of probe K1 increased upon addition of the selective trivalent cations (switch “ON”), and then was quenched (switch “OFF”) after addition of Na 2 EDTA. Thses processes completed one cycle. Addition of the corresponding trivalent cation restored the fluorescence intensity (again switches “ON”) and was further quenched (again switches “OFF”) after addition of Na 2 EDTA, and that completed the second cycle. Thus, the reversible sensing of trivalent cations Al 3+ , Cr 3+ and Fe 3+ by probe K1 was demonstrated with five consecutive cycles without losing the sensitivity of probe K1 as could be observed from Fig. 6 . Additionally, the response time of the complexes formed between probe K1 and Al 3+ , Cr 3+ , Fe 3+ ions to Na 2 EDTA was monitored (Fig. S21). From the results it could be concluded that the fluorescence bursting process was very rapid. Application of Probe K1 in Molecular Logic Gate Four inputs, viz., Al 3+ , Cr 3+ , Fe 3+ and Na 2 EDTA, and one output, the fluorescence intensity at 534 nm were utilized in the trivalent cation-selective sensing experiments. Fluorescence intensities of probe K1 in presence of Al 3+ , Cr 3+ , Fe 3+ and Na 2 EDTA were showed in Fig. 7 . The system was considered to be either as the “ON” state if the fluorescence emission intensity at 534 nm (FI 534 ) was larger than 5.0 × 10 5 (a.u.) or as the “OFF” state if otherwise. The presence of any one or more of the trivalent cation(s) solely led to the fluorescence “ON” (value of “1” ) situation, and if any one of this combination was fed with Na 2 EDTA, the system was “OFF” (value of “0” ). By virtue of the information, a group of basic logic functions, viz., “OR” (presence of any one or more of the trivalent metal ions) and “NOT” (presence of Na 2 EDTA), were fabricated as per that given in the logic circuit as showed in Fig. 8 . The related data were listed in Table 1 . A combination of “ON” and “NOT” from the table afforded the logic gate “AND”. Thus, this molecular logic gate was basically termed as INHIBIT logic gate. Table 1 The input and output for the INHIBIT logic gate IN 1 (Al 3+ ) IN 2 (Cr 3+ ) IN 3 (Fe 3+ ) IN 4 (Na 2 EDTA) output FI 534 0 0 0 0 0 (low) 0 0 0 1 0 (low) 1 0 0 0 1 (high) 1 0 0 1 0 (low) 0 1 0 0 1 (high) 0 1 0 1 0 (low) 0 0 1 0 1 (high) 0 0 1 1 0 (low) 1 1 0 0 1 (high) 0 1 1 0 1 (high) 1 0 1 0 1 (high) 1 1 1 0 1 (high) 0 1 1 1 0 (low) 1 1 1 1 0 (low) Application of Probe K1 in Real Water Samples The utility of probe K1 in determination of the concentrations of Al 3+ , Cr 3+ , Fe 3+ in real water samples was tested. Different water samples were obtained by adding different amounts of Al 3+ , Cr 3+ , Fe 3+ to the water samples taken from Jingyue Lake, Donghua University and piped water. Fluorescence emission spectra of probe K1 (20 µM) in DMSO/H 2 O (9:1) before and after addition of 20 µM of different metal ions (Li + , Na + , K + , Ag + , Cu 2+ , Fe 2+ , Zn 2+ , Co 2+ , Ni 2+ , Mn 2+ , Sr 2+ , Hg 2+ , Ca 2+ , Mg 2+ , Al 3+ , Cr 3+ , Fe 3+ , Ce 3+ , Bi 3+ and Au 3+ ) with the excitation wavelength being 406 nm were measured and showed in Fig. 9 . The concentrations of Al 3+ , Cr 3+ , Fe 3+ in the samples were then measured with probe K1 . The amounts of Al 3+ , Cr 3+ , Fe 3+ added to different water samples, the recoveries and the relative standard deviation (RSD) values were listed in Table 2 , Table S1 and Table S2, respectively. The results showed that the recoveries of Al 3+ , Cr 3+ , Fe 3+ were 99.3–101.1% for Al 3+ , 98.2–101.1% for Cr 3+ and 98.9–100.8% for Fe 3+ , respectively. The RSD values were less than 1.05%. These results demonstrated that probe K1 was reliable and qualified for quantitative determination of Al 3+ , Cr 3+ , Fe 3+ in real water samples. Table 2 Determination of Al 3+ concentrations in real water samples in DMSO/H 2 O (9:1) by probe K1 Sample Added amount (µM) Recovery (%) RSD (%) The Jingyue Lake water The Jingyue Lake water The Jingyue Lake water 2.5 99.6 0.80 5 100 1.04 10 99.3 0.73 Piped water Piped water Piped water 2.5 100.8 1.00 5 99.8 0.51 10 101.1 0.99 Performance Comparison of K1 with Other Specific Al 3+ , Cr 3+ , Fe 3+ Fluorescent Probes Comparison of the sensing performance of probe K1 with other fluorescent chemosensors specific for Al 3+ , Cr 3+ , Fe 3+ in terms of excitation and emission wavelength, test medium, detection limit, response time, and applicable pH range was outlined in Table 3 . From the table it could be seen that probe PAOP [ 14 ], CMN [ 41 ] and PE [ 47 ] responded to common trivalent ions very rapidly. Probe Tb-TCPP showed low detection limit of 7.79–16.4 nM [ 56 ]. however, these probes could not be used in aqueous medium. Rhodamine-based probe L was applicable in an aqueous solution over a wide pH range of 2–10, but it displayed very poor detection limit of 1.9–3.5 × 10 –3 M [ 48 ]. Based on the data in the table, it was concluded that probe K1 had the following advantages over other Al 3+ , Cr 3+ and Fe 3+ fluorescent chemosensors: (1) High specificity and good anti-interference performance for Al 3+ , Cr 3+ and Fe 3+ sensing; (2) Rapid response to Al 3+ , Cr 3+ and Fe 3+ ions within 25 s; (3) Utility in an aqueous medium in a broad pH scale of pH 4–10. Table 3 Comparison of sensing performance of probe K1 with other reported specific Al 3+ , Cr 3+ and Fe 3+ fluorescent probes Probe λ ex /λ em (nm) Medium LOD for Hg 2+ Response time Applicable pH range Reference PAOP 365/445 EtOH 10.10–41.40 µM 5 s – [ 14 ] Rb-SSC 565/590 DMF/H 2 O (4:6) 27.4–62.3 nM 50 s 4–9 [ 18 ] Jb2 450/520 MeOH/H 2 O (8:2) 0.70–2.29 µM – 4–7 [ 33 ] sensor L 409/530 MeOH/H 2 O (1:3) 0.35–3.8 µM – 5–9 [ 40 ] CMN 438/509 MeOH 0.65–0.69 µM 10 s – [ 41 ] SBPQ 460/675 CH 3 CN/HEPES (1:1) 32.4–93.3 nM – 6–10 [ 44 ] probe 1 330/430 THF/H 2 O (8:2) 0.36–0.38 nM – 6.8–7.2 [ 45 ] probe L 520/586 CH 3 CN/Tris (1:1) 0.32–25.5 µM 1 min 5–8 [ 46 ] PE 395/500 CH 3 CN 0.106–0.117 µM 1 min 6–8 [ 47 ] rhodamine probe L 530/588 MeOH/Tris (8:2) 1.9–3.5 mM – 2–10 [ 48 ] HL 500/552 MeOH/H 2 O (7:3) 1.18–4.04 nM – 5–9 [ 49 ] HL 5 510/555 MeOH/HEPES (1:1) 0.29–0.34 µM – 4–8 [ 50 ] RDP 500/560 EtOH/H 2 O (1:1) 1.17–3.16 µM 20 min 4–8 [ 51 ] HL-CHO 500/550 MeOH/HEPES (9:1) 6.97–15.80 nM – 3–8 [ 52 ] L' 502/558 CH 3 CN/H 2 O (1:4) 1.28–2.28 µM – 4–8 [ 53 ] JXUST-2 394/530 DMA 0.10–0.13 µM ~ 15 min – [ 54 ] MO-SP 500/625 EtOH/H 2 O (1:1) 4.39–4.89 µM ~ 7 min – [ 55 ] Tb-TCPP 428/652 DMF 7.79–16.4 nM – 3–9 [ 56 ] (L) 353/458 MeOH/HEPES (6:4) 0.79 nM–1.28 µM 1 min 6–10 [ 57 ] L 3 502/558 CH 3 CN/H 2 O (7:3) 0.47–2.57 µM – 4.5–8 [ 58 ] K1 406/534 DMSO/H 2 O (9:1) 0.27–0.81 µM 25 s 4–10 this work Conclusions In summary, this paper reported a new fluorescent probe based on a naphthalimide derivative for the simultaneous selective detection of Al 3+ , Cr 3+ and Fe 3+ . The probe could be used for the absorption spectral determination of Al 3+ , Cr 3+ and Fe 3+ in DMSO/H 2 O (9:1). Fluorescence emission of the probe was significantly enhanced by Al 3+ , Cr 3+ and Fe 3+ , and the probe exhibited good immunity to interference from the common competitive metal ions (Li + , Na + , K + , Ag + , Cu 2+ , Fe 2+ , Zn 2+ , Co 2+ , Ni 2+ , Mn 2+ , Sr 2+ , Hg 2+ , Ca 2+ , Mg 2+ , Ce 3+ , Bi 3+ and Au 3+ ), with detection limits of 0.32 µM, 0.81 µM, and 0.27 µM for Al 3+ , Cr 3+ , and Fe 3+ , respectively. The probe displayed prompt response to Al 3+ , Cr 3+ and Fe 3+ ions within 25 s and was applicable for real water samples in a broad pH range of pH 4–10. Furthermore, utility of the probe to logic gate by using four inputs, viz., Al 3+ , Cr 3+ , Fe 3+ and Na 2 EDTA, and one output, the fluorescence intensity at 534 nm was achieved. The probe had the advantages of high specificity and sensitivity, large Stokes shift, rapid response, and applicability in various conditions for the simultaneous detection of Al 3+ , Cr 3+ and Fe 3+ . This approach might provide useful reference and help for the development of efficient fluorescent sensors for the selective detection of trivalent metals. Declarations Author Declarations Availability of data and materials: Yes, our manuscript has data included as electronic supplementary material. Competing interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Funding: The Funding for the Open Research Program of State Key Laboratory of Molecular Engineering of Polymers, Fudan University (K2022-38 to Yanxi Song) is acknowledged. Authors' contributions (all authors should be included): Ziyun Lin, Yanxi Song and Hongqi Li wrote the main manuscript text; Ziyun Lin and Yu Shi performed research and analyzed the data. Jiabao Yan and Chengxiao Xie prepared the figures. All authors reviewed the manuscript. Code availability (software application or custom code): Not applicable. Ethics Approval: Not applicable. Consent to Participate: Not applicable. Consent to Publication: Not applicable. References Perl DP, Gajdusek DC, Garruto RM, Yanagihara RT, Gibbs CJ (1982). Intraneuronal aluminum accumulation in amyotrophic lateral sclerosis and parkinsonism-dementia of Guam. Science 217: 1053–1055. https://doi.org/10. 1126/science.7112111. Crapper D, Krishnan SS, Dalton AJ (2022). Brain aluminum distribution in Alzheimer's disease and experimental neurofibrillary degeneration. Science 180: 511–513. https://doi.org/10.1126/science.180.4085.511. Sun Q, Li Y, Shi L, Hussain R, Mehmood K, Tang Z, Zhang H (2022). 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Additional Declarations No competing interests reported. Supplementary Files Scheme1.png Scheme 1 Synthetic route to probe K1 Supplementarymaterial.doc Cite Share Download PDF Status: Published Journal Publication published 11 Jan, 2025 Read the published version in Journal of Fluorescence → Version 1 posted Editorial decision: Revision requested 02 Dec, 2024 Reviews received at journal 29 Nov, 2024 Reviews received at journal 26 Nov, 2024 Reviews received at journal 25 Nov, 2024 Reviewers agreed at journal 21 Nov, 2024 Reviewers agreed at journal 20 Nov, 2024 Reviewers agreed at journal 19 Nov, 2024 Reviewers agreed at journal 19 Nov, 2024 Reviewers agreed at journal 19 Nov, 2024 Reviewers invited by journal 19 Nov, 2024 Editor assigned by journal 10 Nov, 2024 Submission checks completed at journal 10 Nov, 2024 First submitted to journal 04 Nov, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Li","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAyklEQVRIiWNgGAWjYBACAwhpwcPPkANiMROtRYJHsoE0LQwSDAYHiNVizt57+MWbAgkZ4+O5xyQYKqwTG9jPHsCrxbLnXJrlHKDDzM68S5NgOJOe2MCTl4DfYTdyzIx5QFqADAnGtsOJDRI8BsRpMZ4B0vKPOC3Gj0FaDCRAWhqI0XLmjBkjyC8SZ94YWyQcSzdu48khoOV4j/GHN39s7PnbcwxvfKixlu1nP4NfCxCwSfDAmAkgLiH1QMD8gYewolEwCkbBKBjJAABbGz36ofp6vwAAAABJRU5ErkJggg==","orcid":"","institution":"Donghua University","correspondingAuthor":true,"prefix":"","firstName":"Hongqi","middleName":"","lastName":"Li","suffix":""},{"id":382957809,"identity":"bc6c5e45-08ad-4417-bacd-0c123b5e73eb","order_by":5,"name":"Chengxiao Xie","email":"","orcid":"","institution":"Donghua University","correspondingAuthor":false,"prefix":"","firstName":"Chengxiao","middleName":"","lastName":"Xie","suffix":""}],"badges":[],"createdAt":"2024-11-04 08:23:23","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5386144/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5386144/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s10895-024-04130-9","type":"published","date":"2025-01-11T15:57:04+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":70003752,"identity":"c62b07b8-15c4-4291-b3f1-438000125502","added_by":"auto","created_at":"2024-11-27 12:04:50","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":808429,"visible":true,"origin":"","legend":"\u003cp\u003eUV-vis absorption (a), fluorescence emission (excitation wavelength 406 nm) spectra (b), and color changes under 365 nm UV lamp irradiation (c) of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 μM) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) before and after addition of 20 μM of different metal ions (Li\u003csup\u003e+\u003c/sup\u003e, Na\u003csup\u003e+\u003c/sup\u003e, K\u003csup\u003e+\u003c/sup\u003e, Ag\u003csup\u003e+\u003c/sup\u003e, Cu\u003csup\u003e2+\u003c/sup\u003e, Fe\u003csup\u003e2+\u003c/sup\u003e, Zn\u003csup\u003e2+\u003c/sup\u003e, Co\u003csup\u003e2+\u003c/sup\u003e, Ni\u003csup\u003e2+\u003c/sup\u003e, Mn\u003csup\u003e2+\u003c/sup\u003e, Sr\u003csup\u003e 2+\u003c/sup\u003e, Hg\u003csup\u003e2+\u003c/sup\u003e, Ca\u003csup\u003e2+\u003c/sup\u003e, Mg\u003csup\u003e2+\u003c/sup\u003e, Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e, Ce\u003csup\u003e3+\u003c/sup\u003e, Bi\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e)\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/0d21a45c5385acc994a801b1.png"},{"id":70003609,"identity":"ed35afeb-d331-493c-ba31-3b6cb61d0548","added_by":"auto","created_at":"2024-11-27 11:56:50","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":100906,"visible":true,"origin":"","legend":"\u003cp\u003eChanges in the fluorescence intensity at 534 nm of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 μM) with time after addition of Cr\u003csup\u003e3+ \u003c/sup\u003eions (20 μM) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1)\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/b91df1c1ec84b28a24fb4005.png"},{"id":70003607,"identity":"333e9ce1-c6f6-43fe-9c02-2aeef9035bff","added_by":"auto","created_at":"2024-11-27 11:56:50","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":88312,"visible":true,"origin":"","legend":"\u003cp\u003eJob's plot based on the fluorescence intensity at 534 nm versus the molar fraction of Fe\u003csup\u003e3+\u003c/sup\u003e in probe \u003cstrong\u003eK1\u003c/strong\u003e solution containing Fe\u003csup\u003e3+\u003c/sup\u003e in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) with the total concentration of \u003cstrong\u003eK1\u003c/strong\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e being 20 μM.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/27e48999e201684595dad8e4.png"},{"id":70003756,"identity":"93baaeb3-f1a5-4146-a3a7-c34931877335","added_by":"auto","created_at":"2024-11-27 12:04:50","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":254193,"visible":true,"origin":"","legend":"\u003cp\u003eFluorescence intensities at 534 nmm of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 μM) and the mixture of probe \u003cstrong\u003eK1\u003c/strong\u003e with equivalent Al\u003csup\u003e3+\u003c/sup\u003e (20 μM) at different pH conditions (pH 1–14)\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/8adaee825df8efb4ec40a439.png"},{"id":70003605,"identity":"867586b5-a5bb-472f-a4a4-83dccb271094","added_by":"auto","created_at":"2024-11-27 11:56:50","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":166281,"visible":true,"origin":"","legend":"\u003cp\u003ePossible sensing mechanism of probe \u003cstrong\u003eK1\u003c/strong\u003e for Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e ions\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/109faf7b9d4cf4ec5396765a.png"},{"id":70003614,"identity":"0c5155c5-0bb9-4eb5-b489-ccb5573b88c5","added_by":"auto","created_at":"2024-11-27 11:56:50","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":187580,"visible":true,"origin":"","legend":"\u003cp\u003eReversible sensing of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e by probe \u003cstrong\u003eK1\u003c/strong\u003e up to five cycles. Herein the Y axis displays the fluorescence intensity and the increase in fluorescence represents the “ON” state, while the decrease in fluorescence denotes the “OFF” state\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/3cd53c86f01773510ee62d3b.png"},{"id":70003753,"identity":"4a9ebf3c-0f54-45f2-a304-7789cc98edfe","added_by":"auto","created_at":"2024-11-27 12:04:50","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":171541,"visible":true,"origin":"","legend":"\u003cp\u003eHistogram of fluorescence intensities at 534 nm of probe \u003cstrong\u003eK1\u003c/strong\u003e in presence of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e and Na\u003csub\u003e2\u003c/sub\u003eEDTA. Herein the x-axis refers to the boolean expression for construction of INHIBIT logic gate\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/24aec4545141ca234d86ac6f.png"},{"id":70003611,"identity":"33421445-c848-4f1c-8e9c-cc2488842756","added_by":"auto","created_at":"2024-11-27 11:56:50","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":296330,"visible":true,"origin":"","legend":"\u003cp\u003eSchematic representation of the INHIBIT molecular logic circuit with “INx” representing the input, and “FI\u003csub\u003e534\u003c/sub\u003e” denoting the fluorescence intensity as the output\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/dbed0f351a43088db958fc35.png"},{"id":70003755,"identity":"5d387e3c-b0c1-47eb-9213-0997a963dcdd","added_by":"auto","created_at":"2024-11-27 12:04:50","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":189288,"visible":true,"origin":"","legend":"\u003cp\u003eFluorescence emission (excitation wavelength 406 nm) spectra of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 μM) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) before and after addition of 20 μM of different metal ions (Li\u003csup\u003e+\u003c/sup\u003e, Na\u003csup\u003e+\u003c/sup\u003e, K\u003csup\u003e+\u003c/sup\u003e, Ag\u003csup\u003e+\u003c/sup\u003e, Cu\u003csup\u003e2+\u003c/sup\u003e, Fe\u003csup\u003e2+\u003c/sup\u003e, Zn\u003csup\u003e2+\u003c/sup\u003e, Co\u003csup\u003e2+\u003c/sup\u003e, Ni\u003csup\u003e2+\u003c/sup\u003e, Mn\u003csup\u003e2+\u003c/sup\u003e, Sr\u003csup\u003e2+\u003c/sup\u003e, Hg\u003csup\u003e2+\u003c/sup\u003e, Ca\u003csup\u003e2+\u003c/sup\u003e, Mg\u003csup\u003e2+\u003c/sup\u003e, Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e, Ce\u003csup\u003e3+\u003c/sup\u003e, Bi\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e)\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/3ebe80b7b4e073171dbfe23e.png"},{"id":73694713,"identity":"ff41bdd2-2e0e-4e3c-b3d6-45729b461efc","added_by":"auto","created_at":"2025-01-13 16:13:41","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3979746,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/ff2bedec-2548-4c4b-bc10-a2bef5609683.pdf"},{"id":70003612,"identity":"2209f5d4-6d00-41ad-afcb-0525ad782fac","added_by":"auto","created_at":"2024-11-27 11:56:50","extension":"png","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":90462,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eScheme 1\u003c/strong\u003e \u0026nbsp;Synthetic route to probe \u003cstrong\u003eK1\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Scheme1.png","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/8b201a5087951973ac412066.png"},{"id":70005266,"identity":"7f3c8a15-a1a0-4ca8-8ca9-cdea73eedc8c","added_by":"auto","created_at":"2024-11-27 12:12:50","extension":"doc","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":2077184,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementarymaterial.doc","url":"https://assets-eu.researchsquare.com/files/rs-5386144/v1/76ac683049a5e71c391edc45.doc"}],"financialInterests":"No competing interests reported.","formattedTitle":"Sensitive fluorescent probe for Al 3+ , Cr 3+ and Fe 3+ : application in real water samples and logic gate","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAs widely used metal ions, trivalent metal ions, especially Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e are closely related to human health. Aluminium is one of the most abundant elements on earth and is widely used in engineering, automotive industry, batteries, water purification and other fields. However, Al\u003csup\u003e3+\u003c/sup\u003e is not an essential trace element and excessive intake can cause adverse effects on the haematopoietic system, the immune system, the liver and the kidneys, as well as a series of diseases, such as Parkinson's syndrome and Alzheimer's disease [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Chromium is one of the essential trace elements for human growth and development, but a high concentration of Cr\u003csup\u003e3+\u003c/sup\u003e will affect the activity of enzymes in the body, destroy the cellular structure, lead to a loss of balance in redox, impede the normal work of the body's antioxidant system, damage the skin, liver, intestines, respiratory system, etc., leading to skin erythema, ulcers, oedema, etc., and cause swelling of the nasal mucous membranes, headache, shortness of breath, loss of olfactory sensation, nasal haemorrhage and other hazards [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Iron is the most abundant of the essential trace elements in the human body and plays a very important role in physiological activities such as transport and storage of oxygen, synthesis of pigments and some metalloenzymes in cells, and enhancement of immune function [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Iron deficiency can lead to dysfunction of several systemic organs such as the haematological system, digestive system, circulatory system and nervous system. Excess iron can also cause serious conditions such as tissue damage, liver and spleen dysfunction, tumors and even death [\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Therefore, it is of great importance to establish effective methods for the detection of the above three metal ions. Currently, X-ray photoelectron spectroscopy (XPS), atomic spectrometry, mass spectrometry, and inductively coupled plasma emission spectroscopy (ICP) are commonly used in the chemical and biological fields to detect metal ions [\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. These methods are efficient, rapid and accurate, but they are difficult and limited in detection of trivalent metal ions because of the need for large-scale equipment and complex operation. Fluorescent molecular probes are widely used for the detection of various metal ions because of their high sensitivity, good selectivity, short response time and direct observation. At present, some fluorescent probes have been reported for simultaneous detection of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e [\u003cspan additionalcitationids=\"CR12 CR13 CR14 CR15 CR16 CR17 CR18 CR19 CR20 CR21\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. A large part of these probes suffer from low selectivity due to the interference from competitive metal cations including divalent ions Zn\u003csup\u003e2+\u003c/sup\u003e [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], Pd\u003csup\u003e2+\u003c/sup\u003e [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], Hg\u003csup\u003e2+\u003c/sup\u003e [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], Cu\u003csup\u003e2+\u003c/sup\u003e [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e], other trivalent cations Ga\u003csup\u003e3+\u003c/sup\u003e, In\u003csup\u003e3+\u003c/sup\u003e, Tl\u003csup\u003e3+\u003c/sup\u003e and Gd\u003csup\u003e3+\u003c/sup\u003e [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e], Ga\u003csup\u003e3+\u003c/sup\u003e and In\u003csup\u003e3+\u003c/sup\u003e [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], Ga\u003csup\u003e3+\u003c/sup\u003e [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e], Ga\u003csup\u003e3+\u003c/sup\u003e, In\u003csup\u003e3+\u003c/sup\u003e and As\u003csup\u003e3+\u003c/sup\u003e [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e], La\u003csup\u003e3+\u003c/sup\u003e and Ce\u003csup\u003e3+\u003c/sup\u003e [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e], Ru\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e], Ga\u003csup\u003e3+\u003c/sup\u003e, In\u003csup\u003e3+\u003c/sup\u003e and Cu\u003csup\u003e2+\u003c/sup\u003e [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e], and anions PO\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e3\u0026ndash;\u003c/sup\u003e [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e], MnO\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e and Cr\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e7\u003c/sub\u003e\u003csup\u003e2\u0026ndash;\u003c/sup\u003e [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e], PO\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e3\u0026ndash;\u003c/sup\u003e, MnO\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e\u0026ndash;\u003c/sup\u003e, Cr\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e7\u003c/sub\u003e\u003csup\u003e2\u0026ndash;\u003c/sup\u003e and C\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e2\u0026ndash;\u003c/sup\u003e [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. Owing to the paramagnetic nature of Fe\u003csup\u003e3+\u003c/sup\u003e and Cr\u003csup\u003e3+\u003c/sup\u003e, many fluorescent probes for common trivalent metal ions show response mode of fluorescence quenching [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan additionalcitationids=\"CR34 CR35\" citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e], which seriously affects the sensitivity of detection. Moreover, the weak coordination ability of Al\u003csup\u003e3+\u003c/sup\u003e ions and robust hydration of Al\u003csup\u003e3+\u003c/sup\u003e ions in water also brings difficulty and challenge in development of fluorescent probes with outstanding selectivity and sensitivity for simultaneous and fast detection of Fe\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Al\u003csup\u003e3+\u003c/sup\u003e ions in aqueous media. Considering that naphthalimide fluorophore has been proved effective platform for construction of fluorogenic chemosensors to detect Fe\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Al\u003csup\u003e3+\u003c/sup\u003e ions [\u003cspan additionalcitationids=\"CR38 CR39 CR40\" citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e], and trivalent metal ions prefer a multi-dentate ligand to mono- or bi-dentate ligand, we designed and synthesized a new probe \u003cb\u003eK1\u003c/b\u003e by introducing N-hydroxyethyl piperazine and hydroxyethyl ethylenediamine groups into the 1,8-naphthalic anhydride skeleton to endow the system with multi-dentate coordination sites and improved solubility. The developed probe displayed high stability, good water-solubility, and excellent specificity and sensitivity towards trivalent Fe\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Al\u003csup\u003e3+\u003c/sup\u003e ions in aqueous solution. Herein we report the synthesis, characterization, sensing performance, and application in real water samples and logic gate of the new fluorogenic probe.\u003c/p\u003e"},{"header":"Experimental","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003eMaterials and Instruments\u003c/h2\u003eThe chemicals, reagents and solvents were of analytical purity and were purchased from commercial channels, putting into use without further purification unless otherwise stated. Melting points were obtained on an AWRS-2A capillary melting instrument with the quoted temperatures being uncorrected. \u003csup\u003e1\u003c/sup\u003eH nuclear magnetic resonance (\u003csup\u003e1\u003c/sup\u003eH NMR) and \u003csup\u003e13\u003c/sup\u003eC NMR spectra were recorded on a Bruker AM 400 spectrometer. Dimethyl sulfoxide-d\u003csub\u003e6\u003c/sub\u003e (DMSO-d\u003csub\u003e6\u003c/sub\u003e) was used as solvent and chemical shift recorded was internally referenced to tetramethylsilane (Me\u003csub\u003e4\u003c/sub\u003eSi). Infrared (IR) spectra were determined on a Thermo Fisher Scientific Nicolet 380 Fourier Transform (FT) IR spectrophotometer. Mass spectra were recorded on an Agilent 6000 LC\u0026ndash;MS instrument using electronspray ionization (ESI) mode. Fluorescence and ultraviolet-visible (UV-vis) spectra were obtained on a Hitachi F-4500 spectrofluorometer and a JASCO V530 spectrometer, respectively.\n\u003c/div\u003e\n\u003ch3\u003eSynthesis of Compound 1\u003c/h3\u003e\n\u003cp\u003eTo a flask was added 4-bromo-1,8-naphthalic anhydride (1.000 g, 3.61 mmol), N-hydroxyethyl piperazine (0.940 g, 7.22 mmol), and ethylene glycol monomethyl ether (8 mL). The mixture was refluxed at 130\u0026deg;C overnight. After reaction, the reaction solution was slowly added dropwise to 50 mL of water, filtered and washed with water to obtain compound \u003cstrong\u003e1\u003c/strong\u003e as a yellow solid (0.880 g, 74.7%). Mp: 116\u0026ndash;117\u0026deg;C. \u003csup\u003e1\u003c/sup\u003eH NMR (400 MHz, DMSO-d\u003csub\u003e6\u003c/sub\u003e): \u0026delta; 8.47 (d, J\u0026thinsp;=\u0026thinsp;7.7 Hz, 2H), 8.39 (d, J\u0026thinsp;=\u0026thinsp;8.1 Hz, 1H), 7.82 (t, J\u0026thinsp;=\u0026thinsp;7.9 Hz, 1H), 7.33 (d, J\u0026thinsp;=\u0026thinsp;8.2 Hz, 1H), 4.50 (s, 1H), 3.58 (t, J\u0026thinsp;=\u0026thinsp;6.3 Hz, 2H), 3.30 (s, 4H), 2.75 (t, J\u0026thinsp;=\u0026thinsp;4.7 Hz, 4H), 2.54 (t, J\u0026thinsp;=\u0026thinsp;6.2 Hz, 2H).\u003c/p\u003e\n\u003ch3\u003eSynthesis of Probe K1\u003c/h3\u003e\n\u003cp\u003eAnhydrous ethanol (30 mL) was added to a flask containing compound \u003cstrong\u003e1\u003c/strong\u003e (1.648 g, 5.05 mmol) and hydroxyethyl ethylenediamine (0.531 g, 5.10 mmol). The mixture was refluxed at 80\u0026deg;C for 6 h. The progress of the reaction was monitored by thin layer chromatography (TLC) and upon completion of the reaction, the filtrate was withdrawn, the filtrate was spun dry, recrystallized from ether and withdrawn to give probe \u003cstrong\u003eK1\u003c/strong\u003e as a yellow solid (1.39 g, 67.1%). Mp: 122\u0026ndash;123\u0026deg;C. \u003csup\u003e1\u003c/sup\u003eH NMR (400 MHz, DMSO-d\u003csub\u003e6\u003c/sub\u003e): \u0026delta; 8.45\u0026ndash;8.32 (m, 3H), 7.77 (t, J\u0026thinsp;=\u0026thinsp;7.9 Hz, 1H), 7.28 (d, J\u0026thinsp;=\u0026thinsp;8.1 Hz, 1H), 4.52 (s, 2H), 4.10 (t, J\u0026thinsp;=\u0026thinsp;6.9 Hz, 2H), 3.59 (t, J\u0026thinsp;=\u0026thinsp;6.2 Hz, 2H), 3.42 (t, J\u0026thinsp;=\u0026thinsp;5.7 Hz, 2H), 3.21 (t, J\u0026thinsp;=\u0026thinsp;4.7 Hz, 3H), 2.79 (t, J\u0026thinsp;=\u0026thinsp;6.9 Hz, 2H), 2.74 (t, J\u0026thinsp;=\u0026thinsp;4.7 Hz, 4H), 2.62 (t, J\u0026thinsp;=\u0026thinsp;5.7 Hz, 2H), 2.54 (s, 2H), 1.94 (s, 1H). \u003csup\u003e13\u003c/sup\u003eC NMR (101 MHz, DMSO-d\u003csub\u003e6\u003c/sub\u003e): \u0026delta; 163.93, 163.39, 155.89, 132.42, 130.84, 130.66, 129.36, 126.15, 125.50, 122.82, 115.76, 115.14, 60.79, 60.69, 59.06, 53.61, 53.07, 51.87, 47.30. HR-MS: m/z 413.2172 (M\u003csup\u003e+\u003c/sup\u003e + H); calcd. for C\u003csub\u003e22\u003c/sub\u003eH\u003csub\u003e29\u003c/sub\u003eN\u003csub\u003e4\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e 413.2189.\u003c/p\u003e\n\u003ch3\u003eMeasurement of Absorption and Fluorescence Spectra\u003c/h3\u003e\n\u003cp\u003eProbe \u003cstrong\u003eK1\u003c/strong\u003e was dissolved in N,N-dimethylformamide (DMF) to prepare a stock solution (20 \u0026micro;M) for spectral measurement. Before fluorescence emission and UV-vis absorption spectral tests, the salts including LiNO\u003csub\u003e3\u003c/sub\u003e, NaNO\u003csub\u003e3\u003c/sub\u003e, KNO\u003csub\u003e3\u003c/sub\u003e, AgNO\u003csub\u003e3\u003c/sub\u003e, Cu(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e\u0026middot;3H\u003csub\u003e2\u003c/sub\u003eO, FeSO\u003csub\u003e4\u003c/sub\u003e\u0026middot;7H\u003csub\u003e2\u003c/sub\u003eO, Zn(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e\u0026middot;6H\u003csub\u003e2\u003c/sub\u003eO, Co(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e\u0026middot;6H\u003csub\u003e2\u003c/sub\u003eO, NiCl\u003csub\u003e2\u003c/sub\u003e\u0026middot;6H\u003csub\u003e2\u003c/sub\u003eO, Mn(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e\u0026middot;4H\u003csub\u003e2\u003c/sub\u003eO, SrCl\u003csub\u003e2\u003c/sub\u003e\u0026middot;6H\u003csub\u003e2\u003c/sub\u003eO, Hg(OAc)\u003csub\u003e2\u003c/sub\u003e, CaCl\u003csub\u003e2\u003c/sub\u003e, MgCl\u003csub\u003e2\u003c/sub\u003e, Al(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e\u0026middot;9H\u003csub\u003e2\u003c/sub\u003eO, CrCl\u003csub\u003e3\u003c/sub\u003e\u0026middot;6H\u003csub\u003e2\u003c/sub\u003eO, Fe(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e3\u003c/sub\u003e\u0026middot;9H\u003csub\u003e2\u003c/sub\u003eO, CeCl\u003csub\u003e3\u003c/sub\u003e, BiCl\u003csub\u003e3\u003c/sub\u003e and K(AuCl\u003csub\u003e4\u003c/sub\u003e) were dissolved in deionized water. The concentration of these stock solutions was 20 \u0026micro;M. For the fluorescence spectral test, the excitation wavelength was 406 nm, and the excitation and emission slits were both 10.0 nm.\u003c/p\u003e"},{"header":"Results and Discussion","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003eSynthesis of Probe K1\u003c/h2\u003e\n \u003cp\u003eThe synthetic route to the new probe \u003cstrong\u003eK1\u003c/strong\u003e is showed in Scheme \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. Compound \u003cstrong\u003e1\u003c/strong\u003e was synthesized and characterized following the methodology of literature [\u003cspan class=\"CitationRef\"\u003e42\u003c/span\u003e]. Nucleophilic substitution reaction of the two compounds in ethylene glycol monomethyl ether gave compound \u003cstrong\u003e1\u003c/strong\u003e in 74% yield. Nucleophilic addition-elimination reaction of compound \u003cstrong\u003e1\u003c/strong\u003e with hydroxyethyl ethylenediamine in anhydrous ethanol gave the target probe \u003cstrong\u003eK1\u003c/strong\u003e in 67% yield. The chemical structure of \u003cstrong\u003eK1\u003c/strong\u003e was fully characterized by FT-IR (Fig. \u003cspan class=\"InternalRef\"\u003eS1\u003c/span\u003e), \u003csup\u003e1\u003c/sup\u003eH NMR (Fig. S2), \u003csup\u003e13\u003c/sup\u003eC NMR (Fig. S3), and mass spectrometry (Fig. S4). In the IR spectrum, the peak at 3296 cm\u003csup\u003e‒1\u003c/sup\u003e is attributed to the O‒H and N‒H stretching vibration. The band located at 3083 cm\u003csup\u003e‒1\u003c/sup\u003e is ascribed to the stretching vibration of the C‒H bond on the phenyl rings. The peak at 2822 cm\u003csup\u003e‒1\u003c/sup\u003e is originated from C‒H bond stretching vibrations and the band at 1641 cm\u003csup\u003e‒1\u003c/sup\u003e is attributed to the C\u0026thinsp;=\u0026thinsp;O stretching vibration. The peaks at 1588 cm\u003csup\u003e‒1\u003c/sup\u003e and 1513 cm\u003csup\u003e‒1\u003c/sup\u003e are caused by C\u0026thinsp;=\u0026thinsp;C bond stretching vibration. The peaks at 1348 cm\u003csup\u003e‒1\u003c/sup\u003e and 1232 cm\u003csup\u003e‒1\u003c/sup\u003e are originated from C‒N bond stretching vibration. The bands at 1132 cm\u003csup\u003e‒1\u003c/sup\u003e and 1037 cm\u003csup\u003e‒1\u003c/sup\u003e are attributed to the C‒O stretching vibration. The peaks at 780 cm\u003csup\u003e‒1\u003c/sup\u003e and 758 cm\u003csup\u003e‒1\u003c/sup\u003e are caused by C‒H bond bending vibration. In the proton NMR spectrum, the signals at 8.45\u0026ndash;8.32, 7.77 and 7.28 ppm are ascribed to the protons on the naphthylimide ring. The chemical shifts of the methylene protons appeared at 4.52, 4.10, 3.59, 3.42, 2.79 and 2.62 ppm. The signal of the active proton on OH group appeared at 1.94 ppm (singlet). All the spectral data were consistent with the structure of \u003cstrong\u003eK1\u003c/strong\u003e.\u003c/p\u003e\n \u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eFluorescence Spectra of Probe K1 in Different Media\u003c/h3\u003e\n\u003cp\u003eFluorescence spectra of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) in different solvents including DMF, DMSO, ethanol (EtOH), water (H\u003csub\u003e2\u003c/sub\u003eO), and acetonitrile (MeCN) were determined (Fig. S5), from which it was seen that while probe \u003cstrong\u003eK1\u003c/strong\u003e showed the strongest fluorescent emission in deionised water, the difference in fluorescence emission intensity of probe \u003cstrong\u003eK1\u003c/strong\u003e in different organic solvents was not significant. Subsequent tests showed that probe \u003cstrong\u003eK1\u003c/strong\u003e failed to show high selectivity for metal ions in H\u003csub\u003e2\u003c/sub\u003eO and EtOH. However, probe \u003cstrong\u003eK1\u003c/strong\u003e was able to specifically recognize trivalent metal ions in DMSO, so the latter was chosen as the organic medium for sensing performance test. In the course of investigating the suitability of probe \u003cstrong\u003eK1\u003c/strong\u003e in aqueous solution, it was found that probe \u003cstrong\u003eK1\u003c/strong\u003e exhibited steady fluorescence emission and good selectivity for trivalent metal ions in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1, v/v), which was used as the medium in the following detection tests.\u003c/p\u003e\n\u003ch3\u003eFluorogenic Response of Probe K1 to Al, Cr and Fe\u003c/h3\u003e\n\u003cp\u003eChanges in UV-vis absorption and fluorescence emission spectra of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) upon addition of 20 \u0026micro;M of different metal ions (Li\u003csup\u003e+\u003c/sup\u003e, Na\u003csup\u003e+\u003c/sup\u003e, K\u003csup\u003e+\u003c/sup\u003e, Ag\u003csup\u003e+\u003c/sup\u003e, Cu\u003csup\u003e2+\u003c/sup\u003e, Fe\u003csup\u003e2+\u003c/sup\u003e, Zn\u003csup\u003e2+\u003c/sup\u003e, Co\u003csup\u003e2+\u003c/sup\u003e, Ni\u003csup\u003e2+\u003c/sup\u003e, Mn\u003csup\u003e2+\u003c/sup\u003e, Sr \u003csup\u003e2+\u003c/sup\u003e, Hg\u003csup\u003e2+\u003c/sup\u003e, Ca\u003csup\u003e2+\u003c/sup\u003e, Mg\u003csup\u003e2+\u003c/sup\u003e, Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e, Ce\u003csup\u003e3+\u003c/sup\u003e, Bi\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e) were recorded as showed in Fig.\u0026nbsp;1. Addition of common trivalent Fe\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Al\u003csup\u003e3+\u003c/sup\u003e ions caused distinct blue shift in the absorption spectrum of probe \u003cstrong\u003eK1\u003c/strong\u003e solution. While addition of other metal ions failed to bring about substantial change in the absorption spectrum of probe \u003cstrong\u003eK1\u003c/strong\u003e. Addition of Fe\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Al\u003csup\u003e3+\u003c/sup\u003e ions into probe \u003cstrong\u003eK1\u003c/strong\u003e solution resulted in significant enhancement of fluorescence emission intensity in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1), while addition of other metal ions including trivalent Ce\u003csup\u003e3+\u003c/sup\u003e, Bi\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e did not cause significant change in the fluorescence emission. The fluorescence quantum yields of probe \u003cstrong\u003eK1\u003c/strong\u003e and its complexes with Fe\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Al\u003csup\u003e3+\u003c/sup\u003e were measured by using Rhodamine B (\u003cem\u003e\u0026Phi;\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.69) as the standard [\u003cspan class=\"CitationRef\"\u003e43\u003c/span\u003e]. Probe \u003cstrong\u003eK1\u003c/strong\u003e exhibited a low quantum yield of 0.005. The complexes formed between probe \u003cstrong\u003eK1\u003c/strong\u003e and Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e, respectively displayed a \u003cem\u003e\u0026Phi;\u003c/em\u003e value of 0.49, 0.33, 0.63, respectively. Therefore, \u003cstrong\u003eK1\u003c/strong\u003e can be used as a fluorescence turn-on probe for the detection of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e in an aqueous solution.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFigure\u0026nbsp;1\u003c/strong\u003e UV-vis absorption (a), fluorescence emission (excitation wavelength 406 nm) spectra (b), and color changes under 365 nm UV lamp irradiation (c) of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) before and after addition of 20 \u0026micro;M of different metal ions (Li\u003csup\u003e+\u003c/sup\u003e, Na\u003csup\u003e+\u003c/sup\u003e, K\u003csup\u003e+\u003c/sup\u003e, Ag\u003csup\u003e+\u003c/sup\u003e, Cu\u003csup\u003e2+\u003c/sup\u003e, Fe\u003csup\u003e2+\u003c/sup\u003e, Zn\u003csup\u003e2+\u003c/sup\u003e, Co\u003csup\u003e2+\u003c/sup\u003e, Ni\u003csup\u003e2+\u003c/sup\u003e, Mn\u003csup\u003e2+\u003c/sup\u003e, Sr \u003csup\u003e2+\u003c/sup\u003e, Hg\u003csup\u003e2+\u003c/sup\u003e, Ca\u003csup\u003e2+\u003c/sup\u003e, Mg\u003csup\u003e2+\u003c/sup\u003e, Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e, Ce\u003csup\u003e3+\u003c/sup\u003e, Bi\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e)\u003c/p\u003e\n\u003cp\u003eIn order to investigate the interference of other metal ions on the selective detection of Al\u003csup\u003e3+\u003c/sup\u003e by probe \u003cstrong\u003eK1\u003c/strong\u003e, the changes in fluorescence intensity at 534 nm of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) after addition of Al\u003csup\u003e3+\u003c/sup\u003e (20 \u0026micro;M) and/or other competitive metal ions (20 \u0026micro;M) were obtained (Fig. S6). It could be seen that Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e interfered with the selective detection of Al\u003csup\u003e3+\u003c/sup\u003e because \u003cstrong\u003eK1\u003c/strong\u003e was able to detect these three ions at the same time, and the addition of Ce\u003csup\u003e3+\u003c/sup\u003e, Bi\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e also brought about interference, but the fluorescence detection of Al\u003csup\u003e3+\u003c/sup\u003e could still be achieved. Similarly, the changes in fluorescence intensity at 534 nm of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) after addition of Cr\u003csup\u003e3+\u003c/sup\u003e or Fe\u003csup\u003e3+\u003c/sup\u003e (20 \u0026micro;M) and/or other competing metal ions (20 \u0026micro;M) were also recorded as showed in Fig. S7 and Fig. S8, respectively. The results indicated that addition of competitive metal ions including Mn\u003csup\u003e2+\u003c/sup\u003e, Al\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e, Ce\u003csup\u003e3+\u003c/sup\u003e, Bi\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e caused interference to the selective of Cr\u003csup\u003e3+\u003c/sup\u003e. While the existence of competitive metal ions including Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Ce\u003csup\u003e3+\u003c/sup\u003e, Bi\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e interfered with the selective detection of Fe\u003csup\u003e3+\u003c/sup\u003e by probe \u003cstrong\u003eK1\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eTitration of probe \u003cstrong\u003eK1\u003c/strong\u003e with Al\u003csup\u003e3+\u003c/sup\u003e concentration was carried out. Fluorescence emission spectra of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) were measured after addition of different concentrations of Al\u003csup\u003e3+\u003c/sup\u003e (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 \u0026micro;M). Variation of fluorescence intensity at 534 nm of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) with Al \u003csup\u003e3+\u003c/sup\u003e concentration (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 \u0026micro;M) was obtained (Fig. S9). The intensity of the fluorescence emission band was plotted linearly against the concentration of Al\u003csup\u003e3+\u003c/sup\u003e added to probe \u003cstrong\u003eK1\u003c/strong\u003e, which showed a gradual increase in fluorescence intensity as the concentration of added Al\u003csup\u003e3+\u003c/sup\u003e increased from 2 \u0026micro;M to 20 \u0026micro;M. The linear fitting equation was Y\u0026thinsp;=\u0026thinsp;357242.2X \u0026ndash; 16584500.0 with R\u003csup\u003e2\u003c/sup\u003e of 0.992. The limit of detection (LOD) of probe \u003cstrong\u003eK1\u003c/strong\u003e for Al\u003csup\u003e3+\u003c/sup\u003e was calculated to be 0.32 \u0026micro;M according to the equation L\u0026thinsp;=\u0026thinsp;3S/K, where L is the limit of detection, S denotes the standard deviation of the fluorescence intensity of the blank and K represents the slope of the calibration curve.\u003c/p\u003e\n\u003cp\u003eSimilarly, titration of probe \u003cstrong\u003eK1\u003c/strong\u003e with Cr\u003csup\u003e3+\u003c/sup\u003e or Fe\u003csup\u003e3+\u003c/sup\u003e concentration was carried out. Fluorescence emission spectra of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) after addition of different concentrations of Cr\u003csup\u003e3+\u003c/sup\u003e (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 \u0026micro;M) were determined and variation of fluorescence intensity at 534 nm of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) with Cr \u003csup\u003e3+\u003c/sup\u003e concentration (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 \u0026micro;M) was obtained (Fig. S10). The intensity of the fluorescence emission at 534 nm increased as the concentration of added Cr\u003csup\u003e3+\u003c/sup\u003e increased from 2 \u0026micro;M to 20 \u0026micro;M. The linear fitting equation was Y\u0026thinsp;=\u0026thinsp;140582.3X \u0026ndash; 6694646.6 with R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.994. The detection limit of probe \u003cstrong\u003eK1\u003c/strong\u003e was calculated to be 0.81 \u0026micro;M for Cr\u003csup\u003e3+\u003c/sup\u003e. Fluorescence emission spectra of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) after addition of different concentrations of Fe\u003csup\u003e3+\u003c/sup\u003e (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 \u0026micro;M) were determined and variation of fluorescence intensity at 534 nm of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) with Fe\u003csup\u003e3+\u003c/sup\u003e concentration (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 \u0026micro;M) was showed in Fig. S11, from which it could be seen that the fluorescence intensity at 534 nm gradually increased as the concentration of added Fe\u003csup\u003e3+\u003c/sup\u003e increased from 2 \u0026micro;M to 20 \u0026micro;M. The linear fitting equation was obtained as Y\u0026thinsp;=\u0026thinsp;421080.0X \u0026ndash; 12050800.0 with R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.982 and the detection limit of probe \u003cstrong\u003eK1\u003c/strong\u003e was calculated to be 0.27 \u0026micro;M for Fe\u003csup\u003e3+\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eTo investigate the response time of probe \u003cstrong\u003eK1\u003c/strong\u003e to the trivalent cations, variation of fluorescence intensity of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) at 534 nm with time after addition of Al\u003csup\u003e3+\u003c/sup\u003e (20 \u0026micro;M) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) was obtained (Fig. S12). It was seen that the fluorescence intensity increased sharply within the first 15 s upon Al\u003csup\u003e3+\u003c/sup\u003e addition and then increased gradually and very slowly, indicating that probe \u003cstrong\u003eK1\u003c/strong\u003e was sensitive to Al\u003csup\u003e3+\u003c/sup\u003e and suitable for the rapid detection of Al\u003csup\u003e3+\u003c/sup\u003e. Similarly, the change of fluorescence intensity of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) at 534 nm with time after addition of Cr\u003csup\u003e3+\u003c/sup\u003e (20 \u0026micro;M) was recorded in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e, from which it was found that the fluorescence intensity increased sharply within the first 25 s after Cr\u003csup\u003e3+\u003c/sup\u003e was added, and then remained essentially stabilized for 125 s, indicating that probe \u003cstrong\u003eK1\u003c/strong\u003e was sensitive to Cr\u003csup\u003e3+\u003c/sup\u003e and qualified for the rapid detection of Cr\u003csup\u003e3+\u003c/sup\u003e. Changes of fluorescence intensity of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) at 534 nm with time after addition of Fe\u003csup\u003e3+\u003c/sup\u003e (20 \u0026micro;M) was recorded in Fig. S13, from which it was found that the fluorescence intensity increased sharply within the first 15 s after Fe\u003csup\u003e3+\u003c/sup\u003e was added, and then declined to gradually stabilize at 25 s, indicating that probe \u003cstrong\u003eK1\u003c/strong\u003e was sensitive to Fe\u003csup\u003e3+\u003c/sup\u003e and was a good candidate for rapid detection of Fe\u003csup\u003e3+\u003c/sup\u003e. Therefore, probe \u003cstrong\u003eK1\u003c/strong\u003e probe displayed high sensitivity to the common trivalent cations Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e and could be used for the rapid detection of these ions.\u003c/p\u003e\n\u003cp\u003eIn order to investigate the sensing mechanism of probe \u003cstrong\u003eK1\u003c/strong\u003e for the detection of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e, and to understand the coordination pattern between probe \u003cstrong\u003eK1\u003c/strong\u003e and Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e, Job\u0026apos;s plots were drawn. Changes of the fluorescence intensity at 534 nm with the molar fraction of Fe\u003csup\u003e3+\u003c/sup\u003e in probe \u003cstrong\u003eK1\u003c/strong\u003e solution containing Fe\u003csup\u003e3+\u003c/sup\u003e in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) were determined, as showed in Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e. It could be seen that probe \u003cstrong\u003eK1\u003c/strong\u003e formed 1:1 stoichiometric complex with Fe\u003csup\u003e3+\u003c/sup\u003e. Similarly, changes of the fluorescence intensity at 534 nm with the molar fraction of Al\u003csup\u003e3\u0026thinsp;+\u003c/sup\u003e\u0026thinsp;or Cr\u003csup\u003e3+\u003c/sup\u003e in probe \u003cstrong\u003eK1\u003c/strong\u003e solution containing Al\u003csup\u003e3\u0026thinsp;+\u003c/sup\u003e\u0026thinsp;or Cr\u003csup\u003e3+\u003c/sup\u003e in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) were obtained (Fig. S14 and Fig. S15, respectively), which demonstrated that the stoichiometric ratio of probe \u003cstrong\u003eK1\u003c/strong\u003e-Al\u003csup\u003e3+\u003c/sup\u003e and probe \u003cstrong\u003eK1\u003c/strong\u003e-Cr\u003csup\u003e3+\u003c/sup\u003e complex was 1:1.\u003c/p\u003e\n\u003cp\u003eIn order to investigate the effect of pH on the detection of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e by probe \u003cstrong\u003eK1\u003c/strong\u003e, the test solution of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) was configured in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) at pH 1\u0026ndash;14, respectively. Fluorescence intensities at 534 nmm of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) and the mixture of probe \u003cstrong\u003eK1\u003c/strong\u003e with equivalent Al\u003csup\u003e3+\u003c/sup\u003e (20 \u0026micro;M) at different pH conditions (pH 1\u0026ndash;14) were tested as showed in Fig. \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e. The results revealed that addition of equivalent Al\u003csup\u003e3\u0026thinsp;+\u003c/sup\u003e\u0026thinsp;to probe \u003cstrong\u003eK1\u003c/strong\u003e remarkably enhanced the fluorescence emission intensity of the weakly fluorescent probe \u003cstrong\u003eK1\u003c/strong\u003e at pH 4\u0026ndash;10. Similarly, fluorescence intensities at 534 nmm of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) and the mixture of probe \u003cstrong\u003eK1\u003c/strong\u003e with equivalent Cr\u003csup\u003e3\u0026thinsp;+\u003c/sup\u003e\u0026thinsp;or Fe\u003csup\u003e3+\u003c/sup\u003e (20 \u0026micro;M) at different pH conditions (pH 1\u0026ndash;14) were obtained (Fig. S16 and Fig. S17, respectively), which also indicated that addition of equivalent Cr\u003csup\u003e3\u0026thinsp;+\u003c/sup\u003e\u0026thinsp;and Fe\u003csup\u003e3\u0026thinsp;+\u003c/sup\u003e\u0026thinsp;to probe \u003cstrong\u003eK1\u003c/strong\u003e could enhance the fluorescence intensity of probe \u003cstrong\u003eK1\u003c/strong\u003e at pH 4\u0026ndash;10. Therefore, probe \u003cstrong\u003eK1\u003c/strong\u003e could be used to detect Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) at a wide range of pH 4\u0026ndash;10.\u003c/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n \u003ch2\u003eStudy on the Sensing Mechanism of Probe K1\u003c/h2\u003e\n \u003cp\u003eSensing mechanism of probe \u003cstrong\u003eK1\u003c/strong\u003e towards trivalent Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e ions was proposed as showed in Fig. \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e. The hydroxyethylpiperazine moiety in probe \u003cstrong\u003eK1\u003c/strong\u003e, which acted as a tridentate ligand, could provide multiple coordination sites for complexing with trivalent metal ions in 1:1 stoichiometry, as identified by the above-mensioned Job\u0026rsquo;s plot study. The proposed mechanism was verified by comparison of the proton NMR spectrum of probe \u003cstrong\u003eK1\u003c/strong\u003e with those of the products of the reaction between probe \u003cstrong\u003eK1\u003c/strong\u003e and Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e ions (Fig. S18). The broad signal at 1.94 ppm attributed to the hydroxyl proton in probe \u003cstrong\u003eK1\u003c/strong\u003e disappeared after addition of trivalent Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e ions, which implied the complexation between probe \u003cstrong\u003eK1\u003c/strong\u003e and Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e ions. The complexation hindered the intramolecular charge transfer (ICT) process, thereby enhancing the fluorescence intensity. In addition, HR-MS of the product of the reaction between probe \u003cstrong\u003eK1\u003c/strong\u003e and Al\u003csup\u003e3+\u003c/sup\u003e was measured (Fig. S19) to further support the above sensing mechanism. A characteristic peak appeared at m/z 396.9 (less than m/z 412.2 corresponding to the molecular weight of \u003cstrong\u003eK1\u003c/strong\u003e) was observed. It might be formed by deoxygenation of \u003cstrong\u003eK1\u003c/strong\u003e due to the complexation with Al\u003csup\u003e3+\u003c/sup\u003e, which weakened the C\u0026ndash;O bonding.\u003c/p\u003e\n \u003cp\u003eNext, the reversibility of the sensing process was investigated. The complexes formed between probe \u003cstrong\u003eK1\u003c/strong\u003e and trivalent Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e ions were titrated with ethylenediaminetetraacetic acid disodium salt (Na\u003csub\u003e2\u003c/sub\u003eEDTA). Fluorescence spectra of probe \u003cstrong\u003eK1\u003c/strong\u003e upon addition of trivalent Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e and subsequently Na\u003csub\u003e2\u003c/sub\u003eEDTA were determined, respectively (Fig. S20). The fluorescence emission intensity of probe \u003cstrong\u003eK1\u003c/strong\u003e increased upon addition of the selective trivalent cations (switch \u0026ldquo;ON\u0026rdquo;), and then was quenched (switch \u0026ldquo;OFF\u0026rdquo;) after addition of Na\u003csub\u003e2\u003c/sub\u003eEDTA. Thses processes completed one cycle. Addition of the corresponding trivalent cation restored the fluorescence intensity (again switches \u0026ldquo;ON\u0026rdquo;) and was further quenched (again switches \u0026ldquo;OFF\u0026rdquo;) after addition of Na\u003csub\u003e2\u003c/sub\u003eEDTA, and that completed the second cycle. Thus, the reversible sensing of trivalent cations Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e by probe \u003cstrong\u003eK1\u003c/strong\u003e was demonstrated with five consecutive cycles without losing the sensitivity of probe \u003cstrong\u003eK1\u003c/strong\u003e as could be observed from Fig. \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e. Additionally, the response time of the complexes formed between probe \u003cstrong\u003eK1\u003c/strong\u003e and Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e ions to Na\u003csub\u003e2\u003c/sub\u003eEDTA was monitored (Fig. S21). From the results it could be concluded that the fluorescence bursting process was very rapid.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003eApplication of Probe K1 in Molecular Logic Gate\u003c/h2\u003e\n \u003cp\u003eFour inputs, viz., Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e and Na\u003csub\u003e2\u003c/sub\u003eEDTA, and one output, the fluorescence intensity at 534 nm were utilized in the trivalent cation-selective sensing experiments. Fluorescence intensities of probe \u003cstrong\u003eK1\u003c/strong\u003e in presence of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e and Na\u003csub\u003e2\u003c/sub\u003eEDTA were showed in Fig. \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e. The system was considered to be either as the \u0026ldquo;ON\u0026rdquo; state if the fluorescence emission intensity at 534 nm (FI\u003csub\u003e534\u003c/sub\u003e) was larger than 5.0 \u0026times; 10\u003csup\u003e5\u003c/sup\u003e (a.u.) or as the \u0026ldquo;OFF\u0026rdquo; state if otherwise. The presence of any one or more of the trivalent cation(s) solely led to the fluorescence \u0026ldquo;ON\u0026rdquo; (value of \u0026ldquo;1\u0026rdquo; ) situation, and if any one of this combination was fed with Na\u003csub\u003e2\u003c/sub\u003eEDTA, the system was \u0026ldquo;OFF\u0026rdquo; (value of \u0026ldquo;0\u0026rdquo; ). By virtue of the information, a group of basic logic functions, viz., \u0026ldquo;OR\u0026rdquo; (presence of any one or more of the trivalent metal ions) and \u0026ldquo;NOT\u0026rdquo; (presence of Na\u003csub\u003e2\u003c/sub\u003eEDTA), were fabricated as per that given in the logic circuit as showed in Fig. \u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e. The related data were listed in Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. A combination of \u0026ldquo;ON\u0026rdquo; and \u0026ldquo;NOT\u0026rdquo; from the table afforded the logic gate \u0026ldquo;AND\u0026rdquo;. Thus, this molecular logic gate was basically termed as INHIBIT logic gate.\u003c/p\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\u0026nbsp;\u0026nbsp;\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eThe input and output for the INHIBIT logic gate\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eIN\u003csub\u003e1\u003c/sub\u003e (Al\u003csup\u003e3+\u003c/sup\u003e)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eIN\u003csub\u003e2\u003c/sub\u003e (Cr\u003csup\u003e3+\u003c/sup\u003e)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eIN\u003csub\u003e3\u003c/sub\u003e (Fe\u003csup\u003e3+\u003c/sup\u003e)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eIN\u003csub\u003e4\u003c/sub\u003e (Na\u003csub\u003e2\u003c/sub\u003eEDTA)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eoutput FI\u003csub\u003e534\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0 (low)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0 (low)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (high)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0 (low)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (high)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0 (low)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (high)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0 (low)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (high)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (high)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (high)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 (high)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0 (low)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0 (low)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003e\u003c/p\u003e\n \u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\n \u003ch2\u003eApplication of Probe K1 in Real Water Samples\u003c/h2\u003e\n \u003cp\u003eThe utility of probe \u003cstrong\u003eK1\u003c/strong\u003e in determination of the concentrations of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e in real water samples was tested. Different water samples were obtained by adding different amounts of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e to the water samples taken from Jingyue Lake, Donghua University and piped water. Fluorescence emission spectra of probe \u003cstrong\u003eK1\u003c/strong\u003e (20 \u0026micro;M) in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) before and after addition of 20 \u0026micro;M of different metal ions (Li\u003csup\u003e+\u003c/sup\u003e, Na\u003csup\u003e+\u003c/sup\u003e, K\u003csup\u003e+\u003c/sup\u003e, Ag\u003csup\u003e+\u003c/sup\u003e, Cu\u003csup\u003e2+\u003c/sup\u003e, Fe\u003csup\u003e2+\u003c/sup\u003e, Zn\u003csup\u003e2+\u003c/sup\u003e, Co\u003csup\u003e2+\u003c/sup\u003e, Ni\u003csup\u003e2+\u003c/sup\u003e, Mn\u003csup\u003e2+\u003c/sup\u003e, Sr\u003csup\u003e2+\u003c/sup\u003e, Hg\u003csup\u003e2+\u003c/sup\u003e, Ca\u003csup\u003e2+\u003c/sup\u003e, Mg\u003csup\u003e2+\u003c/sup\u003e, Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e, Ce\u003csup\u003e3+\u003c/sup\u003e, Bi\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e) with the excitation wavelength being 406 nm were measured and showed in Fig. \u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003e. The concentrations of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e in the samples were then measured with probe \u003cstrong\u003eK1\u003c/strong\u003e. The amounts of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e added to different water samples, the recoveries and the relative standard deviation (RSD) values were listed in Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e, Table \u003cspan class=\"InternalRef\"\u003eS1\u003c/span\u003e and Table S2, respectively. The results showed that the recoveries of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e were 99.3\u0026ndash;101.1% for Al\u003csup\u003e3+\u003c/sup\u003e, 98.2\u0026ndash;101.1% for Cr\u003csup\u003e3+\u003c/sup\u003e and 98.9\u0026ndash;100.8% for Fe\u003csup\u003e3+\u003c/sup\u003e, respectively. The RSD values were less than 1.05%. These results demonstrated that probe \u003cstrong\u003eK1\u003c/strong\u003e was reliable and qualified for quantitative determination of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e in real water samples.\u003c/p\u003e\n \u003cdiv align=\"char\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\u0026nbsp;\u0026nbsp;\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eDetermination of Al\u003csup\u003e3+\u003c/sup\u003e concentrations in real water samples in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1) by probe \u003cstrong\u003eK1\u003c/strong\u003e\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSample\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAdded amount (\u0026micro;M)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRecovery (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRSD (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eThe Jingyue Lake water\u003c/p\u003e\n \u003cp\u003eThe Jingyue Lake water\u003c/p\u003e\n \u003cp\u003eThe Jingyue Lake water\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e99.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.80\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e99.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.73\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003ePiped water\u003c/p\u003e\n \u003cp\u003ePiped water\u003c/p\u003e\n \u003cp\u003ePiped water\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e100.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e99.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.51\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e101.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.99\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003e\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\n \u003ch2\u003ePerformance Comparison of K1 with Other Specific Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e Fluorescent Probes\u003c/h2\u003e\n \u003cp\u003eComparison of the sensing performance of probe \u003cstrong\u003eK1\u003c/strong\u003e with other fluorescent chemosensors specific for Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e in terms of excitation and emission wavelength, test medium, detection limit, response time, and applicable pH range was outlined in Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e. From the table it could be seen that probe PAOP [\u003cspan class=\"CitationRef\"\u003e14\u003c/span\u003e], CMN [\u003cspan class=\"CitationRef\"\u003e41\u003c/span\u003e] and PE [\u003cspan class=\"CitationRef\"\u003e47\u003c/span\u003e] responded to common trivalent ions very rapidly. Probe Tb-TCPP showed low detection limit of 7.79\u0026ndash;16.4 nM [\u003cspan class=\"CitationRef\"\u003e56\u003c/span\u003e]. however, these probes could not be used in aqueous medium. Rhodamine-based probe L was applicable in an aqueous solution over a wide pH range of 2\u0026ndash;10, but it displayed very poor detection limit of 1.9\u0026ndash;3.5 \u0026times; 10\u003csup\u003e\u0026ndash;3\u003c/sup\u003e M [\u003cspan class=\"CitationRef\"\u003e48\u003c/span\u003e]. Based on the data in the table, it was concluded that probe \u003cstrong\u003eK1\u003c/strong\u003e had the following advantages over other Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e fluorescent chemosensors: (1) High specificity and good anti-interference performance for Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e sensing; (2) Rapid response to Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e ions within 25 s; (3) Utility in an aqueous medium in a broad pH scale of pH 4\u0026ndash;10.\u0026nbsp;\u003c/p\u003e\u0026nbsp;\u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison of sensing performance of probe \u003cstrong\u003eK1\u003c/strong\u003e with other reported specific Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e fluorescent probes\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eProbe\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u0026lambda;\u003csub\u003eex\u003c/sub\u003e/\u0026lambda;\u003csub\u003eem\u003c/sub\u003e (nm)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMedium\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eLOD for Hg\u003csup\u003e2+\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eResponse time\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eApplicable pH range\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eReference\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePAOP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e365/445\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEtOH\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10.10\u0026ndash;41.40 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5 s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eRb-SSC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e565/590\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDMF/H\u003csub\u003e2\u003c/sub\u003eO (4:6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27.4\u0026ndash;62.3 nM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e50 s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u0026ndash;9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eJb2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e450/520\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMeOH/H\u003csub\u003e2\u003c/sub\u003eO (8:2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.70\u0026ndash;2.29 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u0026ndash;7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e33\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003esensor L\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e409/530\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMeOH/H\u003csub\u003e2\u003c/sub\u003eO (1:3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.35\u0026ndash;3.8 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e40\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCMN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e438/509\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMeOH\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.65\u0026ndash;0.69 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10 s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e41\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSBPQ\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e460/675\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCH\u003csub\u003e3\u003c/sub\u003eCN/HEPES (1:1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e32.4\u0026ndash;93.3 nM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u0026ndash;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e44\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eprobe 1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e330/430\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTHF/H\u003csub\u003e2\u003c/sub\u003eO (8:2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.36\u0026ndash;0.38 nM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.8\u0026ndash;7.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e45\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eprobe L\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e520/586\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCH\u003csub\u003e3\u003c/sub\u003eCN/Tris (1:1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.32\u0026ndash;25.5 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e46\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e395/500\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCH\u003csub\u003e3\u003c/sub\u003eCN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.106\u0026ndash;0.117 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u0026ndash;8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e47\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003erhodamine probe L\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e530/588\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMeOH/Tris (8:2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.9\u0026ndash;3.5 mM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u0026ndash;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e48\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e500/552\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMeOH/H\u003csub\u003e2\u003c/sub\u003eO (7:3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.18\u0026ndash;4.04 nM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e49\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHL\u003csup\u003e5\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e510/555\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMeOH/HEPES (1:1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.29\u0026ndash;0.34 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u0026ndash;8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e50\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eRDP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e500/560\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEtOH/H\u003csub\u003e2\u003c/sub\u003eO (1:1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.17\u0026ndash;3.16 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20 min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u0026ndash;8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e51\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHL-CHO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e500/550\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMeOH/HEPES (9:1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.97\u0026ndash;15.80 nM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u0026ndash;8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e52\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eL\u0026apos;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e502/558\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCH\u003csub\u003e3\u003c/sub\u003eCN/H\u003csub\u003e2\u003c/sub\u003eO (1:4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.28\u0026ndash;2.28 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u0026ndash;8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e53\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eJXUST-2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e394/530\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDMA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.10\u0026ndash;0.13 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e~\u0026thinsp;15 min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e54\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMO-SP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e500/625\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEtOH/H\u003csub\u003e2\u003c/sub\u003eO (1:1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.39\u0026ndash;4.89 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e~\u0026thinsp;7 min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e55\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTb-TCPP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e428/652\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDMF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.79\u0026ndash;16.4 nM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u0026ndash;9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e56\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e(L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e353/458\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMeOH/HEPES (6:4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.79 nM\u0026ndash;1.28 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1 min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u0026ndash;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e57\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eL\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e502/558\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCH\u003csub\u003e3\u003c/sub\u003eCN/H\u003csub\u003e2\u003c/sub\u003eO (7:3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.47\u0026ndash;2.57 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026ndash;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.5\u0026ndash;8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e[\u003cspan class=\"CitationRef\"\u003e58\u003c/span\u003e]\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eK1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e406/534\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.27\u0026ndash;0.81 \u0026micro;M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25 s\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u0026ndash;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ethis work\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\n\u003c/div\u003e"},{"header":"Conclusions","content":"\u003cp\u003eIn summary, this paper reported a new fluorescent probe based on a naphthalimide derivative for the simultaneous selective detection of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e. The probe could be used for the absorption spectral determination of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1). Fluorescence emission of the probe was significantly enhanced by Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e, and the probe exhibited good immunity to interference from the common competitive metal ions (Li\u003csup\u003e+\u003c/sup\u003e, Na\u003csup\u003e+\u003c/sup\u003e, K\u003csup\u003e+\u003c/sup\u003e, Ag\u003csup\u003e+\u003c/sup\u003e, Cu\u003csup\u003e2+\u003c/sup\u003e, Fe\u003csup\u003e2+\u003c/sup\u003e, Zn\u003csup\u003e2+\u003c/sup\u003e, Co\u003csup\u003e2+\u003c/sup\u003e, Ni\u003csup\u003e2+\u003c/sup\u003e, Mn\u003csup\u003e2+\u003c/sup\u003e, Sr\u003csup\u003e2+\u003c/sup\u003e, Hg\u003csup\u003e2+\u003c/sup\u003e, Ca\u003csup\u003e2+\u003c/sup\u003e, Mg\u003csup\u003e2+\u003c/sup\u003e, Ce\u003csup\u003e3+\u003c/sup\u003e, Bi\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e), with detection limits of 0.32 µM, 0.81 µM, and 0.27 µM for Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, and Fe\u003csup\u003e3+\u003c/sup\u003e, respectively. The probe displayed prompt response to Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e ions within 25 s and was applicable for real water samples in a broad pH range of pH 4–10. Furthermore, utility of the probe to logic gate by using four inputs, viz., Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, Fe\u003csup\u003e3+\u003c/sup\u003e and Na\u003csub\u003e2\u003c/sub\u003eEDTA, and one output, the fluorescence intensity at 534 nm was achieved. The probe had the advantages of high specificity and sensitivity, large Stokes shift, rapid response, and applicability in various conditions for the simultaneous detection of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e. This approach might provide useful reference and help for the development of efficient fluorescent sensors for the selective detection of trivalent metals.\u003c/p\u003e "},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor Declarations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAvailability of data and materials: Yes, our manuscript has data included as electronic supplementary material.\u003c/p\u003e\n\u003cp\u003eCompeting interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e\n\u003cp\u003eFunding: The Funding for the Open Research Program of State Key Laboratory of Molecular Engineering of Polymers, Fudan University (K2022-38 to Yanxi Song) is acknowledged.\u003c/p\u003e\n\u003cp\u003eAuthors\u0026apos; contributions (all authors should be included): Ziyun Lin, Yanxi Song and Hongqi Li wrote the main manuscript text; Ziyun Lin and Yu Shi performed research and analyzed the data. Jiabao Yan and Chengxiao Xie prepared the figures. All authors reviewed the manuscript.\u003c/p\u003e\n\u003cp\u003eCode availability (software application or custom code): Not applicable.\u003c/p\u003e\n\u003cp\u003eEthics Approval: Not applicable.\u003c/p\u003e\n\u003cp\u003eConsent to Participate: Not applicable.\u003c/p\u003e\n\u003cp\u003eConsent to Publication: Not applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003ePerl DP, Gajdusek DC, Garruto RM, Yanagihara RT, Gibbs CJ (1982). Intraneuronal aluminum accumulation in amyotrophic lateral sclerosis and parkinsonism-dementia of Guam.\u003cem\u003e \u003c/em\u003eScience 217: 1053\u0026ndash;1055. https://doi.org/10. 1126/science.7112111.\u003c/li\u003e\n\u003cli\u003eCrapper D, Krishnan SS, Dalton AJ (2022). Brain aluminum distribution in Alzheimer\u0026apos;s disease and experimental neurofibrillary degeneration. 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Inorganic Chemistry Communications 117: 107968. https://doi.org/10.1016/j.inoche.2020.107968.\u003c/li\u003e\n\u003cli\u003eFu C, Sun X, Zhang G, Shi P, Cui P (2021). Porphyrin-based metal-organic framework probe: highly selective and sensitive fluorescent turn-on sensor for M\u003csup\u003e3+\u003c/sup\u003e (Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, and Fe\u003csup\u003e3+\u003c/sup\u003e) ions. Inorganic Chemistry 60: 1116\u0026ndash;1123. https://dx. doi.org/10.1021/acs.inorgchem.0c03268.\u003c/li\u003e\n\u003cli\u003eMahata S, Janani G, Mandal BB, Manivannan V (2021). A coumarin based visual and fluorometric probe for selective detection of Al(III), Cr(III) and Fe(III) through \u0026quot;turn-on\u0026quot; response and its biological application. Journal of Photochemistry \u0026amp; Photobiology A: Chemistry 417: 113340. https://doi.org/10. 1016/j.jphotochem.2021.113340.\u003c/li\u003e\n\u003cli\u003eDas D, Alam R, Ali M (2022). Rhodamine 6G-based efficient chemosensor for trivalent metal ions (Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e) upon single excitation with applications in combinational logic circuits and memory devices. Analyst 147: 471\u0026ndash;479. https://doi.org/10.1039/d1an01788h.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Scheme 1","content":"\u003cp\u003eScheme 1 is available in the Supplementary Files section.\u003c/p\u003e\n"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-fluorescence","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jofl","sideBox":"Learn more about [Journal of Fluorescence](https://www.springer.com/journal/10895)","snPcode":"10895","submissionUrl":"https://submission.nature.com/new-submission/10895/3","title":"Journal of Fluorescence","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Fluorescent probe, Trivalent cation, Naphthalimide, Logic gate","lastPublishedDoi":"10.21203/rs.3.rs-5386144/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5386144/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eConstruction of single probes for simultaneous detection of common trivalent metal ions has attracted much attention due to higher efficiency in analysis and cost. A naphthalimide-based fluorescent probe \u003cb\u003eK1\u003c/b\u003e was synthesized for selective detection of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e ions. Fluorescence emission intensity at 534 nm of probe \u003cb\u003eK1\u003c/b\u003e in DMSO/H\u003csub\u003e2\u003c/sub\u003eO (9:1, v/v) was significantly enhanced upon addition of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e ions while addition of other metal ions (Li\u003csup\u003e+\u003c/sup\u003e, Na\u003csup\u003e+\u003c/sup\u003e, K\u003csup\u003e+\u003c/sup\u003e, Ag\u003csup\u003e+\u003c/sup\u003e, Cu\u003csup\u003e2+\u003c/sup\u003e, Fe\u003csup\u003e2+\u003c/sup\u003e, Zn\u003csup\u003e2+\u003c/sup\u003e, Co\u003csup\u003e2+\u003c/sup\u003e, Ni\u003csup\u003e2+\u003c/sup\u003e, Mn\u003csup\u003e2+\u003c/sup\u003e, Sr\u003csup\u003e2+\u003c/sup\u003e, Hg\u003csup\u003e2+\u003c/sup\u003e, Ca\u003csup\u003e2+\u003c/sup\u003e, Mg\u003csup\u003e2+\u003c/sup\u003e, Ce\u003csup\u003e3+\u003c/sup\u003e, Bi\u003csup\u003e3+\u003c/sup\u003e and Au\u003csup\u003e3+\u003c/sup\u003e) did not bring about substantial change in fluorescence emission. The calculated detection limits were 0.32 \u0026micro;M, 0.81 \u0026micro;M, and 0.27 \u0026micro;M for Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e, and Fe\u003csup\u003e3+\u003c/sup\u003e, respectively. Probe \u003cb\u003eK1\u003c/b\u003e displayed strong anti-interference ability, a large Stokes shift, rapid response, and applicability in a wide pH range for the simultaneous detection of Al\u003csup\u003e3+\u003c/sup\u003e, Cr\u003csup\u003e3+\u003c/sup\u003e and Fe\u003csup\u003e3+\u003c/sup\u003e in real water samples. Job's plot test showed that the stoichiometric ratio of the complexes formed between probe \u003cb\u003eK1\u003c/b\u003e and the trivalent metal ions was 1:1. The reversible application of probe \u003cb\u003eK1\u003c/b\u003e was realized by addition of Na\u003csub\u003e2\u003c/sub\u003eEDTA. A molecular logic gate was built based on the input-output information. This approach may provide a basis for highly selective and sensitive detection of common trivalent cations and for design of memory devices.\u003c/p\u003e","manuscriptTitle":"Sensitive fluorescent probe for Al 3+ , Cr 3+ and Fe 3+ : application in real water samples and logic gate","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-11-27 11:56:45","doi":"10.21203/rs.3.rs-5386144/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-12-02T15:53:30+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-11-29T09:29:12+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-11-26T15:19:02+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-11-25T17:29:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"230699553917616117682969828284282981195","date":"2024-11-22T01:19:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"85988665071107106360362780982762362679","date":"2024-11-20T10:50:35+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"329951630147899777482925185972452853622","date":"2024-11-20T04:38:02+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"87537070375967030797586111635159324343","date":"2024-11-19T15:03:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"46952751677640523643156377278239709990","date":"2024-11-19T14:47:38+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-11-19T14:45:24+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-11-11T00:10:14+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-11-11T00:09:06+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Fluorescence","date":"2024-11-04T08:17:37+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-fluorescence","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jofl","sideBox":"Learn more about [Journal of Fluorescence](https://www.springer.com/journal/10895)","snPcode":"10895","submissionUrl":"https://submission.nature.com/new-submission/10895/3","title":"Journal of Fluorescence","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"20f8bfd7-dd4e-4d18-8f94-2a211057060e","owner":[],"postedDate":"November 27th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-01-13T16:10:01+00:00","versionOfRecord":{"articleIdentity":"rs-5386144","link":"https://doi.org/10.1007/s10895-024-04130-9","journal":{"identity":"journal-of-fluorescence","isVorOnly":false,"title":"Journal of Fluorescence"},"publishedOn":"2025-01-11 15:57:04","publishedOnDateReadable":"January 11th, 2025"},"versionCreatedAt":"2024-11-27 11:56:45","video":"","vorDoi":"10.1007/s10895-024-04130-9","vorDoiUrl":"https://doi.org/10.1007/s10895-024-04130-9","workflowStages":[]},"version":"v1","identity":"rs-5386144","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5386144","identity":"rs-5386144","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}