Dual-mode electrochemiluminescence and fluorescence aptasensing platform based on resonance energy transfer for sensitive detection of estradiol

Dual-mode electrochemiluminescence and fluorescence aptasensing platform based on resonance energy transfer for sensitive detection of estradiol | 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 Dual-mode electrochemiluminescence and fluorescence aptasensing platform based on resonance energy transfer for sensitive detection of estradiol Waner Hou, Zhimin Liu, Xuanxuan Hao, Xun Lei, Jintao Cheng, Yaxin Li, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6278066/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 23 May, 2025 Read the published version in Microchimica Acta → Version 1 posted 9 You are reading this latest preprint version Abstract Herein, an electrochemiluminescence (ECL)-fluorescence (FL) dual-mode aptasensing system was proposed for estradiol detection. Firstly, ruthenium-based metal–organic framework nanosheets (RuMOFNSs) were synthesized by a simple one - pot method. RuMOFNSs exhibited both fluorescence (FL) and electrochemiluminescence (ECL) characteristics. After RuMOFNSs were immobilized on the electrode, complementary target DNA (cDNA), gold nanoclusters labeled aptamer (AuNCs-Apt) were successively assembled on the electrode to fabricate the aptasensor. The absorption spectrum of RuMOFNSs could be well overlapped with the fluorescence emission spectrum (or ECL spectrum) of AuNCs. When estradiol was absent, AuNCs-Apt could hybridize with cDNA to form double-stranded DNA, the close proximity between AuNCs and RuMOFNSs led to the efficient resonance energy transfer (RET) from AuNCs (donor) to RuMOFNSs (acceptor), thus the enhanced ECL (or FL) signals was achieved. In the presence of estradiol, the high affinity between Apt and estradiol led to the dissociation of double-stranded DNA, and the increased distance between AuNCs and RuMOFNSs hindered the RET, and the decreased ECL (or FL) signals were obtained. The aptasensor demonstrates exceptional sensitivity for detecting estradiol, with FL and ECL detection limits of 97 pM and 20 fM, respectively. This innovative approach offers significant potential for endocrine-disrupting chemical analysis. RuMOFNSs Dual-mode Electrochemiluminescence Fluorescence Resonance energy transfer Estradiol Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Introduction Estradiol is a natural hormone in both humans and animals, it plays an important role in bone strength, sexual characteristics, and maintaining healthy pregnancy [ 1 ]. Because of its bio-accumulative toxicity, excess estradiol may disturb the endocrine system, causing male infertility, liver damage, and even induce prostate cancer [ 2 , 3 ], so estradiol has been classified as a typical endocrine disrupting compound in a variety of water sources and animal products [ 4 ]. Therefore, monitoring estradiol levels in environmental and food samples is of great clinical significance. To date, various strategies have been successfully developed for estradiol detection, such as high performance liquid chromatography (HPLC) [ 5 , 6 ], gas chromatography coupled with mass spectrometry (GC–MS) [ 7 , 8 ], electrochemistry [ 9 , 10 ], colorimetry [ 11 , 12 ] and fluorescence [ 13 , 14 ]. Noticeably, singular signal output is still the main detection strategy in the reported methods. Although the sensitivity has reached a relatively high level, the false signal generation and poor anti-interference ability may cause inaccurate results in practical detection [ 15 ]. In order to solve the drawbacks of single-mode analysis, the dual-mode sensing systems based on independent signal transduction have aroused considerable interests among researchers. The reported dual signal outputs include electrochemiluminescence (ECL)-colorimetry [ 16 ], fluorescence (FL)-colorimetry [ 17 ], electrochemistry-ECL [ 18 ], photochemistry-FL [ 19 ], and FL-ECL [ 20 ]. The dual-mode system can effectively reduce the risk of false results, which is beneficial for improving the accuracy and reliability of bioassays [ 16 ]. The dual-mode methods such as electrochemiluminescence-electrochemistry and colorimetry-fluorescence have been reported for estradiol assay [ 21 , 22 ]. Considering the sensitivity of multiple roles, considerable efforts are still needed to develop novel multi-mode methods to reliably monitor estradiol in environmental or food samples. The luminescent agent tris(4,4′-dicarboxylic acid-2,2′-bipyridine) ruthenium dichloride(II) (Ru(dcbpy) 3 2+ ), as tris(2,2′-bipyridyl)-ruthenium(II) (Ru(bpy) 3 2+ ) derivative, has been widely applied in biosensor fabrication due to its outstanding optical properties [ 23 ]. However, Ru(dcbpy) 3 2+ shows defects in stability and specificity [ 24 ]. In contrast, ruthenium-based metal–organic framework nanosheets (RuMOFNSs) display significant superiority in developing sensors owing to their and large surface area and high porosity. The unique framework structure of RuMOFNSs enables these nanoclusters with excellent electrochemical and optical properties, which are benefit for keeping the excellent performance of the sensors. Additionally, Ru(dcbpy) 3 2+ is distributed in RuMOFNSs, which can effectively prevent the leakage of ECL luminophore, thereby improving the long-term stability of sensors [ 25 , 26 ]. Gold nanoclusters (AuNCs) own surface plasmon resonance effect [ 27 ], which are crucial to enhance the sensitivity of both ECL and FL sensing modes. Interestingly, reported work showed that ECL resonance energy transfer could occur between AuNCs and Ru(bpy) 3 2+ in the anodic Ru(bpy) 3 2+ ECL systems [ 28 ]. Fluorescence resonance energy transfer (FRET) is a nonradiative energy transfer process, it often happens when a fluorescent donor and an acceptor are brought into close proximity [ 29 , 30 ]. FRET is often applied as an efficient signal-amplification strategy for a variety of bioassays [ 31 ]. Interestingly, Ru(bpy) 3 2+ was also a proper fluorescent acceptor or donor in FRET-based sensors [ 32 , 33 ]. For example, FRET between AuNCs and Ru(bpy) 3 2+ has been reported for fabricating ECL biosensors [ 34 ]. In this work, RuMOFNSs were synthesized and assembled onto the electrode, subsequently, the above electrodes were successively modified with complementary target DNA (c-DNA) and AuNCs labeled aptamer (AuNCs-Apt), accordingly, a dual-mode (ECL and FL) aptasensor was developed. The estradiol assay was accomplished according to the ECL or FL signal changes. When estradiol was absent, the aptamer gene complemented the cDNA base to form a double-stranded structure, AuNCs and RuMOFNSs were in close proximity, efficient RET could happen, resulting in the enhanced ECL (or FL) signals. When dual-mode sensor was incubated with estradiol analyte, estradiol’s specific binding with aptamer induced the increased distance between AuNCs and RuMOFNSs, RET was hampered and a decreased ECL (or FL) signal was obtained. Hence, estradiol can be parallelly quantified by the ECL/FL response. This method was also utilized for detecting estradiol in real samples (river water and milk), and the results exhibited good recoveries for practical applications. Experimental Reagents Tris(4,4′-dicarboxylic acid-2,2′-bipyridine) ruthenium dichloride(II) (Ru(dcbpy) 3 2+ ), estrone and progesterone were purchased from Macklin (Shanghai, China). Estradiol, pyrazine, bovine serum albumin (BSA), bisphenol A, N-hydroxy succinimide (NHS), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC), polyvinyl pyrrolidone (PVP, MW = 58000), Zn(NO 3 ) 2 ·6H 2 O and HAuCl 4 ·4H 2 O were provided by Aladdin (Shanghai, China). Phosphate buffer solution (PBS) was used as electrolyte. All reagents used were of analytical grade and required no further purification. The base sequences were synthesized by Shanghai Biotechnology Corporation, and the sequences are as follows [ 22 ]: Complementary target DNA (cDNA): 5'-GGA GGA GGA GGA GGA GGA GGA GGA GGA GGA GGA GGA GGA GGC TTC CGC GCT TCA GCG CGC AGC AA-NH 2 -(CH 2 ) 6 -3' Estradiol aptamer (Apt): 5'-TTT TTT TTT TTT TTT GCT TCC AGC TTA TTG AAT TAC ACG CAG AGG GTA GCG GCT CTG CGC ATT CAA TTG CTG CGC GCT GAA GCG CGG AAG C-SH-(CH 2 ) 6 -3' Instruments FL measurements were performed on F-7000 fluorescence spectrophotometer (Hitachi, Japan). The ECL was carried out on a ECL detection system (model MPI-A, China).A three-electrode system was employed, containing an Ag/AgCl electrode as the reference electrode, a Pt wire as the auxiliary electrode and a modified GCE (3 mm) as the working electrode. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were acquired from CHI 660E electrochemical workstation (China). X-ray diffraction (XRD) analyses were obtained from MiniFlex 600 (Rigaku, Japan). Scanning electron microscope (SEM, Quanta FEG250, USA) and Transmission electron microscope (TEM, FEI Tecnai G2 F30, USA) were applied to obtain the morphologies. The X-ray photoelectron spectra (XPS) were obtained on 250Xi X-ray photoelectron spectrometer (Thermo, USA). UV–vis absorption spectra were conducted on spectrophotometer (UV-3600, Japan). Preparation of RuMOFNSs We synthesized RuMOFNSs according to the reported method [ 35 ], and the synthesis steps are shown in Scheme 1 A. In a 100 mL round flask, Zn(NO 3 ) 2 ·6H 2 O (18 mg), Ru(dcbpy) 3 2+ (18 mg), pyrazine (3.2 mg) and PVP (40 mg) were added to 64 mL of H 2 O. After sonicating for 10 min, the flask was heated at 80 ℃ for 24 h. The resulting precipitate was centrifuged (12000 rpm, 10 min) and thoroughly washed with water for three times. RuMOFNSs was obtained by drying at 60 ℃ for 8 h. The newly prepared RuMOFNSs (5 mg) was dispersed into 5 mL H 2 O and sonicated for 10 min. Then, 1 mL of EDC (400 mM)/NHS (100 mM) mixture were added and maintained for 2 h under the gently stirring. The activated RuMOFNSs were collected by centrifugal washing and redispersed into water. Preparation of AuNCs AuNCs were synthesized according to the previous research [ 28 ]. As displayed in Scheme 1 B, HAuCl 4 solution (10 mL, 10 mM) was added into BSA (10 mL, 20 mg/mL) and kept stirring vigorously at 37°C. Afterward, ascorbic acid (10 µL, 0.35 mg/mL) was added dropwise, and pH of the solution was adjusted to 8.0 by using NaOH. After vigorous stirring for 5 h, the obtained AuNCs were purified by the dialysis (molecular weight cutoff of 2000 Da) and stored at 4°C for further use. The Apt (12 µL, 100 µM) was incubated with AuNCs (588 µL) and kept at 37°C for 12 h to obtain AuNCs labeled Apt (AuNCs-Apt). Fabrication of the dual-mode aptasensor The ECL sensor assembly is shown in Scheme 1 C. Firstly, 5 µL of activated RuMOFNSs (0.4 mg/mL) was dropped on the GCE electrode, then, 5 µL cDNA(2 µM) was coated on the RuMOFNSs modified electrode and dried in the air. After blocking with BSA, 5 µL of AuNCs-Apt was assembled onto the modified electrode and maintained at 37°C for 40 min. Thereafter, the above modified electrode was incubated with estradiol solution (5 µL) and kept for 2 h at room temperature. Finally, the resulted GCE electrode was coated 5 µL Nafion (5%) to keep the stability of the sensor. Scheme 1 D shows the FL mode detection. Firstly, 20 µL of activated RuMOFNSs was mixed with 20 µL of cDNA (2 µM), and kept at 4°C for 12 h. Next, 20 µL of BSA was added and kept at 37°C for 30 min. Afterward, AuNCs-Apt was added and the reaction was carried out at 37°C for 50 min to complete the hybridization. Subsequently, estradiol was added and incubated at 37°C for 2 h. The resulting solution was stored in a refrigerator at 4°C. Dual -mode measurement of estradiol The FL spectra were recorded at an excitation wavelength of 462 nm and a slit width of 5 nm. The ECL measurement was performed by incubating the aptasensor in a pH 7.0 PBS containing 100 mM K 2 S 2 O 8 , and the potential steps were fixed at -1.5 ~ 0 V with scan rate of 0.1 V/s. Results and discussion Characterization of the nanomaterials The morphologies of RuMOFNSs were characterized by TEM and SEM, which displayed clear and irregular sheet - like structure (Fig. 1 A-C), and the lateral size was 0.51 µm (inset in Fig. 1 C). Meantime, the crystal structure of RuMOFNSs was identified by XRD (Fig. 1 D), the characteristic diffraction peaks were accorded with the reported literature [ 35 ]. XPS spectra were also employed to confirm the elemental composition of RuMOFNSs. As displayed in Fig. S1 A, XPS survey spectrum of RuMOFNSs showed the characteristic peaks of C 1s, O 1s, N 1s, Ru 3p and Zn 2p elements. Particularly, the high - resolution spectrum of Ru 3p (Fig. S1 B) displayed the characteristic peaks of Ru 3p 1/2 (484.5 eV) and Ru 3p 3/2 (462.4 eV), while the Zn 2p (Fig. S1 C) showed two peaks located at 1021.3 eV (Zn 2p 3/2 ) and 1044.5 eV (Zn 2p 1/2 ). The auger electron peak of Zn inserted into the Ru 3p region ascribed to the co -existing of Ru and Zn elements. The synthesis of RuMOFNSs was further confirmed by FT-IR spectrum (Fig. 2 A) and UV-vis absorption spectrum (Fig. 2 B). The characteristic peaks at 1429 − 1372 cm − 1 and 1718 − 1549 cm − 1 ascribed to the antisymmetric and symmetric stretching vibration of COO − , respectively [ 36 , 37 ]. The RuMOFNSs exhibited two obvious peaks at 308 nm and 474 nm (Fig. 2 B, curve a), which are related to the π→π* electron transition of bi-pyridine ring and the dπ(Ru)→π* (dcbpy) metal-to-ligand charge transfer, respectively [ 37 , 38 ]. Compared with the free Ru(dcbpy) 3 2+ ligand (Fig. 2 B, curve b), the absorption peaks of RuMOFNSs showed a slight red shift, which indicating the successful coordination between Zn 2+ and carboxylic groups of Ru(dcbpy) 3 2+ [ 39 ]. Figure 3 A exhibited the FL spectra of AuNCs, an emission peak at 439 nm and an excitation maximum of 380 nm were observed. The HRTEM image of the AuNCs demonstrated that the particle size was around 3.3 nm (Fig. 3 B). Response mechanisms of dual-modal readout platform As shown in Fig. 4 A, RuMOFNSs presented maximum absorption at 478 nm (curve a), while AuNCs had an obvious fluorescence emission spectrum at approximately 439 nm (curve b). The absorption spectrum of RuMOFNSs could be well overlapped with the fluorescence emission spectrum of AuNCs, thus, an efficient FRET from Au NCs to RuMOFNSs was achieved. The fluorescence responses of this sensing platform under different conditions are shown in Fig. 4 B, the RuMOFNSs showed a weak fluorescence signal at 610 nm (curve black). However, for the mixture of RuMOFNSs, cDNA and AuNCs-Apt, FL signal at 610 nm was observed to be significantly increased (curve red), demonstrating the feasibility of FRET between AuNCs and RuMOFNSs. In contrast, when estradiol was added in the mixture of RuMOFNSs, cDNA and AuNCs-Apt, the fluorescence intensity was decreased (curve blue). The reason is that aptamer displayed higher affinity toward estradiol, resulting in the AuNCs-Apt away from RuMOFNSs, and the increased distance between RuMOFNSs and AuNCs blocked the FRET process, thus a decreased FL signal was obtained. Similarly, the ECL responses of the sensing platform under different conditions were investigated in the range of -1.5-0 V in 0.1 M PBS (pH 7.0) with 100 mM K 2 S 2 O 8 (Fig. 4 C). The results showed that RuMOFNSs modified GCE had weak ECL signals. However, the ECL intensities increased when cDNA and Aptamer-AuNCs was successively assembled on RuMOFNSs/GCE. The ECL signal enhancing phenomenon is attributed to the ERET between AuNCs and RuMOFNSs, because the reported maximum ECL emission of AuNCs was observed at 490 nm [ 28 ], we found that the absorption spectrum of RuMOFNSs could be well overlapped with the ECL spectrum of AuNCs, therefore the ERET from AuNC donors to RuMOFNSs acceptors could occur and an increased ECL response was obtained. The following modification of estradiol on AuNCs-Apt/BSA/cDNA/RuMOFNSs/GCE led to the decreased ECL response because of the unsuccessful ERET. Characterization of the Sensing platform The step-by-step construction process of the dual-mode biosensor was monitored by EIS and CV. As depicted in Fig. 5 A, the charge transfer resistance (Rct) value of RuMOFNSs (curve b) was lower than that of the GCE (curve a) because RuMOFNSs blocked the electron transport. With the increased modification of cDNA, BSA and AuNCs-Apt, the increase of the Rct value indicated that these materials hindered the electron transfer channel, resulting in a decrease of the electron transfer rate. In particular, the addition of estradiol led to a significant decrease in Rct value. This change indicates that the higher affinity between Apt and estradiol could release cDNA from AuNCs-Apt, leading to the recovery of the electrode’s electron transfer ability. The CV results (Fig. 5 B) exhibited the same pattern as the EIS analysis, suggesting the effective construction of the dual-mode biosensor. ECL and FL performance evaluation of dual-mode sensors In order to accurately evaluate the sensitivity of the dual-mode sensors, the experimental conditions of ECL and FL measurements were optimized (See supplementary information Fig. S2(A-C) for details of experimental condition optimization). As depicted in Fig. 6 A and C, the ECL and FL signal values gradually decreased with increasing concentration of estradiol in the ranges of and 50 fM to100 nM and 100 pM to 10000 nM, respectively, exhibiting a good linear relationship. The correlation equations were described as follows: for ECL, Y = 6080.03–1439.67 lgC (R 2 = 0.996); and for FL, Y = 3877.17–459.82 lgC (R 2 = 0.997), respectively, as exhibited in Fig. 6 B and D. According to the formula L = 3S b /k 0 (S b : the standard deviation; K 0 : slope of the calibration curve), the ECL and FL detection limits of the sensor were calculated to be 20 fM and 97 pM, respectively. Compared with the reported single-mode detection methods (Table S1 ), this dual-mode sensor provided better detection performance including high sensitivity, low detection limit and simple operation. Selectivity, reproducibility and stability of the aptasensor For selectivity, the ECL (or FL) signals were examined against the estradiol and several interfering substances, including estrone, progesterone, bisphenol A, nitrite, nitrate, sulphate, and mixture. As shown in Fig. 7 A and Fig. 7 B, the estradiol (100 pM) and the mixture of estradiol and other interferents demonstrated similar signal intensity. Moreover, in comparison with the blank solution, the addition of interfering substances (10 nM) did not cause obvious ECL (or FL) signal changes, which happens to prove the good specificity of the sensor. The reproducibility of the aptamer sensor was studied. Six electrodes were measured in parallel, and the relative standard deviations (RSDs) of the final test results were 1.85% for 100 pM estradiol (Fig. 7 C). The stability of ECL signal for 1 nM estradiol was recorded by 16 consecutive cycles, showing an RSD of 1.19% (Fig. 7 D). In summary, these results demonstrated the satisfactory performance of the dual-mode sensor in estradiol analysis. Analysis of estradiol in real sample In order to evaluate the practicality of the aptasensor, real lake water and milk samples were collected and used for recovery analysis. The samples were treated according to the reported work [ 22 ], after that, the samples spiked with various estradiol concentrations were detected by the fabricated ECL-FL system. Table S2 displayed the experiment results, the recoveries of lake water ranged from 99.24 to 104.52% (ECL) and 94.72 to 101.96% (FL), respectively. The recoveries of milk ranged from 95.52 to 100.94% (ECL) and 98.94 to 103.76% (FL), respectively. These findings reveal that the dual-mode platform is a suitable strategy for estradiol assay in practical application. Conclusion In summary, a FL-ECL dual-mode aptasensor platform was constructed by successively assembling cDNA and AuNCs-Apt onto the RuMOFNCs modified electrode. RuMOFNCs exhibited excellent FL and ECL characteristics. The sensitive detection of estradiol was successfully achieved based on resonance energy transfer between AuNCs and RuMOFNCs. Furthermore, this dual-mode sensor can also be employed to detect estradiol in real samples, demonstrating a potential application in food safety fields. Declarations Author contribution Waner Hou: writing-original draft, formal analysis, data curation. Zhimin Liu: writing-review and editing, project administration, funding acquisition. Xuanxuan Hao: Data curation. Xun Lei: formal analysis；Jintao Cheng: visualization, investigation. Yaxin Li: funding acquisition, data curation. Leqian Hu: software, formal analysis. Peng Li: supervision, project administration. Funding This work was financially supported by the National Natural Science Foundation of China (No. 22305068), Natural Science Foundation of Henan (No. 222300420426) and Fund of the Institute of Complexity Science, Henan University of Technology (No. CSKFJJ202543). Data availability No datasets were generated or analysed during the current study. Ethics declarations Competing interest The authors declare that they have no conflict of interests. References Ely C, Moreira IS, Bassin JP, Dezotti MWC, Mesquita DP, Costa J, Ferreira EC, Castro PML (2022) Treatment of saline wastewater amended with endocrine disruptors by aerobic granular sludge: Assessing performance and microbial community dynamics. J Environ Chem Eng 10: 107272. Hamid N, Junaid M, Pei DS (2021) Combined toxicity of endocrine-disrupting chemicals: A review. Ecotoxicol Environ Saf 215: 112136. Nohynek GJ, Borgert CJ, Dietrich D, Rozman KK (2013) Endocrine disruption: fact or urban legend? Toxicol Lett 223: 295-305. Waring RH, Harris RM (2005) Endocrine disrupters: A human risk? Mol Cell Endocrinol 244: 2-9. Lu HZ, Xu SF (2015) Mesoporous structured estrone imprinted Fe 3 O 4 @SiO 2 @ mSiO 2 for highly sensitive and selective detection of estrogens from water samples by HPLC. Talanta 144: 303-311. Tian X, Song HJ, Wang Y, Tian XM, Tang YH, Gao RX, Zhang CX (2020) Hydrophilic magnetic molecularly imprinted nanobeads for efficient enrichment and high performance liquid chromatographic detection of 17beta-estradiol in environmental water samples. Talanta 220: 121367. Sghaier RB, Net S, Ghorbel-Abid I, Bessadok S, Coz ML, Hassan-Chehimi DB, Trabelsi-Ayadi M, Tackx M, Ouddane B (2017) Simultaneous detection of 13 endocrine disrupting chemicals in water by a combination of SPE-BSTFA derivatization and GC-MS in transboundary rivers (France-Belgium). Water Air Soil Poll 228: 1-14. Janssens G, Mangelinckx S, Courtheyn D, Pr´evost S, Poorter GD, Kimpe ND, Bizec BL (2013) Application of gas chromatography-mass spectrometry/ combustion/ isotope ratio mass spectrometry (GC-MS/C/IRMS) to detect the abuse of 17β-Estradiol in cattle. J Agr Food Chem 61: 7242-7249. Mat Zaid MH, Abdullah J, Rozi N. Rozlan AAM, Hanifah SA (2020) A sensitive impedimetric aptasensor based on carbon nanodots modified electrode for detection of 17β-Estradiol. Nanomaterials 10: 1346. Supchocksoonthorn P, Alvior Sinoy MC, de Luna MDG, Paoprasert P (2021) Facile fabrication of 17β-estradiol electrochemical sensor using polyaniline/carbon dot-coated glassy carbon electrode with synergistically enhanced electrochemical stability. Talanta 235: 122782. Alsager OA, Kumar S, Zhu BC, Travas-Sejdic J, McNatty KP, Hodgkiss JM (2015) Ultrasensitive colorimetric detection of 17β-Estradiol: the effect of shortening DNA aptamer sequences. Anal Chem 87: 4201-4209. Pu HB, Huang ZB, Sun DW, Xie XH, Zhou WB (2019) Development of a highly sensitive colorimetric method for detecting 17β-Estradiol based on combination of gold nanoparticles and shortening DNA aptamers. Water Air Soil Poll 230: 1-9. Mehlhorn A, Rahimi P, Joseph Y (2018) Aptamer-based biosensors for antibiotic detection: a review. Biosensors 8: 54. Sha HF, Yan B (2021) Design of a ratiometric fluorescence sensor based on metal organic frameworks and Ru(bpy) 3 2+ -doped silica composites for 17β-Estradiol detection. J Colloid Interf Sci 583: 50-57. Liu P, Zhao MH, Zhu HJ, Zhang ML, Li X, Wang MZ, Liu BX, Pan JM, Niu XH (2022) Dual-mode fluorescence and colorimetric detection of pesticides realized by integrating stimulus-responsive luminescence with oxidase-mimetic activity into cerium-based coordination polymer nanoparticles. J Hazard Mater 423: 127077. Hu Y, Zhu L, Me XC, Liu JS, Yao ZP, Li YC (2021) Dual-mode sensing platform for electrochemiluminescence and colorimetry detection based on a closed bipolar electrode. Anal Chem 93: 12367-12373. He KY, Sun LP, Wang L, Li W, Hu GX, Ji XF, Zhang YM, Xu XH (2022) Engineering DNA G-quadruplex assembly for label-free detection of Ochratoxin A in colorimetric and fluorescent dual modes. J Hazard Mater 423: 126962. Mi XN, Li H, Tan R, Tu YF (2020) Dual-modular aptasensor for detection of cardiac troponin I based on mesoporous silica films by electrochemiluminescence/electrochemical impedance spectroscopy. Anal Chem 92: 14640-14647. Zhang L, Chen FZ, Sun HD, Meng RZ, Zeng QS, Wang XX, Zhou H (2022) Stimulus-responsive metal–organic framework signal-reporting system for photoelectrochemical and fluorescent dual-mode detection of ATP. ACS Appl Mater Interfaces 14: 46103-46111. Hu HT, Cui HF, Yin X, Fan QQ, Shuai H, Zhang J,Liao FS, Xiong W, Jiang HD, Fan H, Liu WM, Wei GB (2024) Dual-mode fluorescence and electrochemiluminescence sensors based on Ru-MOF nanosheets for sensitive detection of apoE genes. J Mater Chem B 12: 701-709. Guo ZH, Yang B, Zhu J, Lou SY, Hao HM, Lu WY (2024) Light-activated, dual-mode fluorescence and colorimetric detection of estradiol with high fidelity based on aptamer’s special recognition. Food Chem 436: 137702. Hou WE, Liu ZM, Hao XX, Zheng TT, Yang XP, Li YX, Hu LQ (2025) Dual-modular electrochemiluminescence/electrochemistry aptasensing platform based on Ru(dcbpy) 3 2+ loaded copper oxide nanospheres and Cu-Au bimetallic nanoparticles for the sensing of estradiol. Microchem J 210: 112893. Hu DD, Zhan TY, Guo ZY, Wang S, Hu YF (2021) Electrosynthesized metal-organic framework: A dual-modality readout platform for Cu (II), coenzyme A and histone acetyltransferase analysis. Sensor Actuat B: Chem 327: 128896. Yu FY, Qin LY, Zhang H, Qin LS, Fan H (2024) A novel fluorescence-electrochemiluminescence dual-mode sensing platform for high-precision BRAF gene detection. Analyst 149: 2114-2121. Yan MX, Ye J, Zhu QJ, Zhu LP, Huang JS, Yang XR (2019) Ultrasensitive immunosensor for cardiac troponin I detection based on the electrochemiluminescence of 2D Ru-MOF nanosheets. Anal Chem 91: 10156-10163. Lu ML, Huang W, Gao SZ, Zhang JL, Liang WB, Li Y, Yuan R, Xiao DR (2022) Pyrene-based hydrogen-bonded organic frameworks as new emitters with porosity-and aggregation-induced enhanced electrochemiluminescence for ultrasensitive microRNA assay. Anal Chem 94: 15832-15838. Ishito N, Nakajima K, Maegawa Y, Inagaki S, Fukuoka A (2017) Facile formation of gold nanoparticles on periodic mesoporous bipyridine-silica. Catal Today 298: 258-262. Yu YC, Lu C, Zhang MN (2015) Gold nanoclusters@Ru(bpy) 3 2+ -layered double hydroxide ultrathin film as a cathodic electrochemiluminescence resonance energy transfer probe. Anal Chem 87: 8026-8032. Liao PL, Zang SH, Wu TY, Jin HJ, Wang WK, Huang JB, Tang BZ, Yan Y (2021) Generating circularly polarized luminescence from clusterization-triggered emission using solid phase molecular self-assembly. Nat Commun 12: 5496. Li MX, Feng QM, Zhou Z, Zhao W, Xu JJ, Chen HY (2018) Plasmon-enhanced electrochemiluminescence for nucleic acid detection based on gold nanodendrites. Anal Chem 90: 1340-347. Li Y, Zhang LB, Zhang Z, Liu Y, Chen J, Liu J, Du PY, Guo HX, Lu XQ (2021) MnO 2 nanospheres assisted by cysteine combined with MnO 2 nanosheets as a fluorescence resonance energy transfer system for “Switch-on” detection of glutathione. Anal Chem 93: 9621-9627. Zhu SM, Wang SC, Xia MM, Wang BJ, Huang Y, Zhang DX, Zhang XJ, Wang GF (2019) Intracellular imaging of glutathione with MnO 2 nanosheet@Ru(bpy) 3 2+ -UiO-66 nanocomposites. ACS Appl Mater Interfaces 11: 31693-31699. Zhan YJ, Luo F, Guo LH, Qiu B, Lin YH, Li J, Chen GN, Lin ZY (2017) Preparation of an efficient ratiometric fluorescent nanoprobe ( m -CDs@[Ru(bpy) 3 ] 2+ ) for visual and specific detection of hypochlorite on site and in living cells. ACS Sens 2: 1684-1691. Feng QM, Xu HW, Li ZB, Chen CF, Miao XM (2022) A novel “signal off-triggered on” Fo¨rster resonance energy transfer biosensor for the ratiometric detection of pathogenic bacteria. Sensor Actuat B: Chem 372: 132598. Kent CA, Mehl BP, Ma LQ, Papanikolas JM, Meyer TJ, Lin WB (2010) Energy transfer dynamics in metal-organic frameworks. J Am Chem Soc132: 12767-12769. Zhao YW, Jiang L, Shangguang L, Mi L, Liu AR, Liu SQ (2018) Synthesis of porphyrin-based two-dimensional metal-organic framework nanodisk with small size and few layers. J Mater Chem A 6: 2828-2833. Xiao FN, Wang M, Wang FB, Xia XH (2014) Graphene-ruthenium (II) complex composites for sensitive ECL immunosensors. Small 10: 706-716. Shi L, Li XJ, Zhu WJ, Wang YG, Du B, Cao W, Wei Q, Pang XH (2017) Sandwich-type electrochemiluminescence sensor for detection of NT-proBNP by using high efficiency quench strategy of Fe 3 O 4 @ PDA toward Ru(bpy) 3 2+ coordinated with silver oxalate. ACS Sens 2: 1774-1778. Zhao MT, Wang YX, Ma QL, Huang Y, Zhang X, Ping JF, Zhang ZC, Lu QP, Yu YF, Xu H, Zhao YL, Zhang H (2015) Ultrathin 2D metal-organic framework nanosheets. Adv Mater 27: 7372-7378. Scheme 1 Scheme 1 is available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Supplentmentarymaterial1.docx floatimage9.jpeg Graphical Abstract floatimage1.png Scheme 1 Preparations of RuMOFNSs (A), AuNCs (B) and their application in ECL-FL dual mode analysis (C, D). Cite Share Download PDF Status: Published Journal Publication published 23 May, 2025 Read the published version in Microchimica Acta → Version 1 posted Editorial decision: Revision requested 13 Apr, 2025 Reviews received at journal 08 Apr, 2025 Reviews received at journal 06 Apr, 2025 Reviewers agreed at journal 28 Mar, 2025 Reviewers agreed at journal 27 Mar, 2025 Reviewers invited by journal 27 Mar, 2025 Editor assigned by journal 25 Mar, 2025 Submission checks completed at journal 25 Mar, 2025 First submitted to journal 21 Mar, 2025 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6278066","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":442357620,"identity":"3b96ea0c-536b-4d18-95a9-a2ece212e1fe","order_by":0,"name":"Waner Hou","email":"","orcid":"","institution":"Henan University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Waner","middleName":"","lastName":"Hou","suffix":""},{"id":442357623,"identity":"1621ac1c-5c57-4f6b-8fbf-c6f2fc04e618","order_by":1,"name":"Zhimin Liu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwklEQVRIiWNgGAWjYDACCcYGhgQGmwQIj414LWlALcxEawGTh0nQIj+7uXXDwx3n8/hn5B9g+FB2mIF/dgN+LYxzDrbdSDxzu1jiRjID44xzhxkk7hzAr4VZIhGope12YgNQCzNv22EGA4kE/FrYIFrOJc4HaflLjBYeiJYDiRtAWhiJ0SIB0ZKcuPHMY4ODPefSeSRuENAiPyP92c2fbXaJ844nPnzwo8xajn8GAS0o4ADIpSSoHwWjYBSMglGACwAApt1H5ySBJUEAAAAASUVORK5CYII=","orcid":"","institution":"Henan University of Technology","correspondingAuthor":true,"prefix":"","firstName":"Zhimin","middleName":"","lastName":"Liu","suffix":""},{"id":442357624,"identity":"bda64fe9-2920-42bf-bf63-d35687b4a777","order_by":2,"name":"Xuanxuan Hao","email":"","orcid":"","institution":"Henan University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Xuanxuan","middleName":"","lastName":"Hao","suffix":""},{"id":442357626,"identity":"bcb917fd-2370-46a1-a088-a340b0e2cfef","order_by":3,"name":"Xun Lei","email":"","orcid":"","institution":"Henan University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Xun","middleName":"","lastName":"Lei","suffix":""},{"id":442357627,"identity":"2bb6559d-45c9-4bf8-9b98-ee73531b9f4f","order_by":4,"name":"Jintao Cheng","email":"","orcid":"","institution":"Henan University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Jintao","middleName":"","lastName":"Cheng","suffix":""},{"id":442357628,"identity":"89e4e2aa-1cd0-4692-8cb0-ab8dd1fa71f6","order_by":5,"name":"Yaxin Li","email":"","orcid":"","institution":"Henan University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Yaxin","middleName":"","lastName":"Li","suffix":""},{"id":442357629,"identity":"a40efd46-fffa-4837-b44a-c0581ff36ac6","order_by":6,"name":"Leqian Hu","email":"","orcid":"","institution":"Henan University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Leqian","middleName":"","lastName":"Hu","suffix":""},{"id":442357630,"identity":"745e6667-c6b0-4061-bbd0-486081a06da1","order_by":7,"name":"Peng Li","email":"","orcid":"","institution":"Henan University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Peng","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2025-03-21 13:38:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6278066/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6278066/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00604-025-07205-x","type":"published","date":"2025-05-23T15:58:07+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":80754787,"identity":"d9e22eca-ad38-4cc6-84b3-223942bdaed6","added_by":"auto","created_at":"2025-04-16 17:32:19","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1032854,"visible":true,"origin":"","legend":"\u003cp\u003eTEM image (A) and SEM images (B, C) of RuMOFNSs. XRD spectra of RuMOFNSs (D).\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6278066/v1/8aa6fe90f9b6b20980eb25e3.png"},{"id":80755769,"identity":"d37fc408-206d-4f08-9d90-5c763cf0780e","added_by":"auto","created_at":"2025-04-16 17:48:19","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":250505,"visible":true,"origin":"","legend":"\u003cp\u003eFT-IR spectra (A) and UV\u003cstrong\u003e-\u003c/strong\u003evis absorption spectra of RuMOFNSs (curve a) and Ru(dcbpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e 2+\u003c/sup\u003e (curve b)\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-6278066/v1/40c2c82ddb44dcb5289a1d0b.png"},{"id":80754792,"identity":"31c6307e-c599-49e4-8443-495f02d2fd6b","added_by":"auto","created_at":"2025-04-16 17:32:19","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":471615,"visible":true,"origin":"","legend":"\u003cp\u003e(A) Excitation (red) and emission (blue) spectra of AuNCs. (B) HRTEM image of AuNCs.\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-6278066/v1/0389e7745f0b476fd86726f0.png"},{"id":80755408,"identity":"61a1f0f8-572f-4c89-b32f-ec3c5b7298a0","added_by":"auto","created_at":"2025-04-16 17:40:19","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":309737,"visible":true,"origin":"","legend":"\u003cp\u003e(A) The UV–vis spectrum of RuMOFNSs (a) and the fluorescence spectrum of Au NCs (b). The effects of different materials on the FL (B) and ECL intensities (C).\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-6278066/v1/7432f567586d3f87fbbd9599.png"},{"id":80755407,"identity":"8b83b462-d0b3-4e8c-9341-3f94416bb70f","added_by":"auto","created_at":"2025-04-16 17:40:19","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":235125,"visible":true,"origin":"","legend":"\u003cp\u003eEIS (A) and CV (B) responses of (a) GCE; (b) RuMOFNSs/GCE; (c) cDNA/RuMOFNSs/GCE; (d) BSA/cDNA/RuMOFNSs/GCE; (e) AuNCs-Apt/BSA/cDNA/RuMOFNSs/GCE; (f) Estradiol/AuNCs-Apt /BSA/cDNA/RuMOFNSs/GCE in 5.0 mM [Fe(CN)\u003csub\u003e6\u003c/sub\u003e]\u003csup\u003e3-/4 \u003c/sup\u003econtaining 0.1 M KCl.\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-6278066/v1/7cd6041e0293fd536bf2baec.png"},{"id":80754794,"identity":"064ed516-8480-4458-ab74-2d171c37d690","added_by":"auto","created_at":"2025-04-16 17:32:19","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":422240,"visible":true,"origin":"","legend":"\u003cp\u003eECL (A) and FL (C) response curves of the aptasensor toward different concentrations of estradiol. The calibration curve of ECL (B) and FL (D) intensities with respect to estradiol concentration.\u003c/p\u003e","description":"","filename":"floatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-6278066/v1/d2b3d4142c6b818a1b36853a.png"},{"id":80754798,"identity":"e5457349-720f-4941-b62d-503e843665a0","added_by":"auto","created_at":"2025-04-16 17:32:20","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":474308,"visible":true,"origin":"","legend":"\u003cp\u003eECL (A) and FL (B) experiments of the aptasensor selectivity (estradiol: 100 pM; interferents: 10 nM). Reproducibility (C) and cyclic stability (D) of the aptasensor for ECL experiments.\u003c/p\u003e","description":"","filename":"floatimage8.png","url":"https://assets-eu.researchsquare.com/files/rs-6278066/v1/0fd76f5c724b65afc9f1f601.png"},{"id":83460658,"identity":"95c372f1-e8cd-4d37-8ad1-0991130bcb75","added_by":"auto","created_at":"2025-05-26 16:13:18","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4532456,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6278066/v1/05fff4fa-6b76-4984-808b-39826cbc47c9.pdf"},{"id":80754791,"identity":"1fee50ad-6883-486e-8698-65d085d8ed0e","added_by":"auto","created_at":"2025-04-16 17:32:19","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":256285,"visible":true,"origin":"","legend":"","description":"","filename":"Supplentmentarymaterial1.docx","url":"https://assets-eu.researchsquare.com/files/rs-6278066/v1/bfcd9ea7e137fcbc5337ff30.docx"},{"id":80755770,"identity":"2db107fd-5eda-4d25-b684-eb467fde3b87","added_by":"auto","created_at":"2025-04-16 17:48:20","extension":"jpeg","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":641243,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eGraphical Abstract\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage9.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6278066/v1/4255a832176f4cb98e244e23.jpeg"},{"id":80755412,"identity":"303db878-5829-4433-87f9-d37038c48e32","added_by":"auto","created_at":"2025-04-16 17:40:20","extension":"png","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":515918,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eScheme 1 \u003c/strong\u003ePreparations of RuMOFNSs (A), AuNCs (B) and their application in ECL-FL dual mode analysis (C, D).\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-6278066/v1/886f3364f8af744c3c0b969b.png"}],"financialInterests":"No competing interests reported.","formattedTitle":"Dual-mode electrochemiluminescence and fluorescence aptasensing platform based on resonance energy transfer for sensitive detection of estradiol","fulltext":[{"header":"Introduction","content":"\u003cp\u003eEstradiol is a natural hormone in both humans and animals, it plays an important role in bone strength, sexual characteristics, and maintaining healthy pregnancy [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Because of its bio-accumulative toxicity, excess estradiol may disturb the endocrine system, causing male infertility, liver damage, and even induce prostate cancer [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], so estradiol has been classified as a typical endocrine disrupting compound in a variety of water sources and animal products [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Therefore, monitoring estradiol levels in environmental and food samples is of great clinical significance. To date, various strategies have been successfully developed for estradiol detection, such as high performance liquid chromatography (HPLC) [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], gas chromatography coupled with mass spectrometry (GC\u0026ndash;MS) [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], electrochemistry [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], colorimetry [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] and fluorescence [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Noticeably, singular signal output is still the main detection strategy in the reported methods. Although the sensitivity has reached a relatively high level, the false signal generation and poor anti-interference ability may cause inaccurate results in practical detection [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn order to solve the drawbacks of single-mode analysis, the dual-mode sensing systems based on independent signal transduction have aroused considerable interests among researchers. The reported dual signal outputs include electrochemiluminescence (ECL)-colorimetry [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e], fluorescence (FL)-colorimetry [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], electrochemistry-ECL [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], photochemistry-FL [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], and FL-ECL [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. The dual-mode system can effectively reduce the risk of false results, which is beneficial for improving the accuracy and reliability of bioassays [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. The dual-mode methods such as electrochemiluminescence-electrochemistry and colorimetry-fluorescence have been reported for estradiol assay [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Considering the sensitivity of multiple roles, considerable efforts are still needed to develop novel multi-mode methods to reliably monitor estradiol in environmental or food samples.\u003c/p\u003e \u003cp\u003eThe luminescent agent tris(4,4\u0026prime;-dicarboxylic acid-2,2\u0026prime;-bipyridine) ruthenium dichloride(II) (Ru(dcbpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e), as tris(2,2\u0026prime;-bipyridyl)-ruthenium(II) (Ru(bpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e) derivative, has been widely applied in biosensor fabrication due to its outstanding optical properties [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. However, Ru(dcbpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e shows defects in stability and specificity [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. In contrast, ruthenium-based metal\u0026ndash;organic framework nanosheets (RuMOFNSs) display significant superiority in developing sensors owing to their and large surface area and high porosity. The unique framework structure of RuMOFNSs enables these nanoclusters with excellent electrochemical and optical properties, which are benefit for keeping the excellent performance of the sensors. Additionally,\u003c/p\u003e \u003cp\u003eRu(dcbpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e is distributed in RuMOFNSs, which can effectively prevent the leakage of ECL luminophore, thereby improving the long-term stability of sensors [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Gold nanoclusters (AuNCs) own surface plasmon resonance effect [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e], which are crucial to enhance the sensitivity of both ECL and FL sensing modes. Interestingly, reported work showed that ECL resonance energy transfer could occur between AuNCs and Ru(bpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e in the anodic Ru(bpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e ECL systems [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eFluorescence resonance energy transfer (FRET) is a nonradiative energy transfer process, it often happens when a fluorescent donor and an acceptor are brought into close proximity [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. FRET is often applied as an efficient signal-amplification strategy for a variety of bioassays [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. Interestingly, Ru(bpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e was also a proper fluorescent acceptor or donor in FRET-based sensors [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. For example, FRET between AuNCs and Ru(bpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e has been reported for fabricating ECL biosensors [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn this work, RuMOFNSs were synthesized and assembled onto the electrode, subsequently, the above electrodes were successively modified with complementary target DNA (c-DNA) and AuNCs labeled aptamer (AuNCs-Apt), accordingly, a dual-mode (ECL and FL) aptasensor was developed. The estradiol assay was accomplished according to the ECL or FL signal changes. When estradiol was absent, the aptamer gene complemented the cDNA base to form a double-stranded structure, AuNCs and RuMOFNSs were in close proximity, efficient RET could happen, resulting in the enhanced ECL (or FL) signals. When dual-mode sensor was incubated with estradiol analyte, estradiol\u0026rsquo;s specific binding with aptamer induced the increased distance between AuNCs and RuMOFNSs, RET was hampered and a decreased ECL (or FL) signal was obtained. Hence, estradiol can be parallelly quantified by the ECL/FL response. This method was also utilized for detecting estradiol in real samples (river water and milk), and the results exhibited good recoveries for practical applications.\u003c/p\u003e"},{"header":"Experimental","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eReagents\u003c/h2\u003e \u003cp\u003eTris(4,4\u0026prime;-dicarboxylic acid-2,2\u0026prime;-bipyridine) ruthenium dichloride(II) (Ru(dcbpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e), estrone and progesterone were purchased from Macklin (Shanghai, China). Estradiol, pyrazine, bovine serum albumin (BSA), bisphenol A, N-hydroxy succinimide (NHS), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC), polyvinyl pyrrolidone (PVP, MW\u0026thinsp;=\u0026thinsp;58000), Zn(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e\u0026middot;6H\u003csub\u003e2\u003c/sub\u003eO and HAuCl\u003csub\u003e4\u003c/sub\u003e\u0026middot;4H\u003csub\u003e2\u003c/sub\u003eO were provided by Aladdin (Shanghai, China). Phosphate buffer solution (PBS) was used as electrolyte. All reagents used were of analytical grade and required no further purification. The base sequences were synthesized by Shanghai Biotechnology Corporation, and the sequences are as follows [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]:\u003c/p\u003e \u003cp\u003eComplementary target DNA (cDNA): 5'-GGA GGA GGA GGA GGA GGA GGA GGA GGA GGA GGA GGA GGA GGC TTC CGC GCT TCA GCG CGC AGC AA-NH\u003csub\u003e2\u003c/sub\u003e-(CH\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e6\u003c/sub\u003e-3'\u003c/p\u003e \u003cp\u003eEstradiol aptamer (Apt): 5'-TTT TTT TTT TTT TTT GCT TCC AGC TTA TTG AAT TAC ACG CAG AGG GTA GCG GCT CTG CGC ATT CAA TTG CTG CGC GCT GAA GCG CGG AAG C-SH-(CH\u003csub\u003e2\u003c/sub\u003e)\u003csub\u003e6\u003c/sub\u003e-3'\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eInstruments\u003c/h3\u003e\n\u003cp\u003eFL measurements were performed on F-7000 fluorescence spectrophotometer (Hitachi, Japan). The ECL was carried out on a ECL detection system (model MPI-A, China).A three-electrode system was employed, containing an Ag/AgCl electrode as the reference electrode, a Pt wire as the auxiliary electrode and a modified GCE (3 mm) as the working electrode. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were acquired from CHI 660E electrochemical workstation (China). X-ray diffraction (XRD) analyses were obtained from MiniFlex 600 (Rigaku, Japan). Scanning electron microscope (SEM, Quanta FEG250, USA) and Transmission electron microscope (TEM, FEI Tecnai G2 F30, USA) were applied to obtain the morphologies. The X-ray photoelectron spectra (XPS) were obtained on 250Xi X-ray photoelectron spectrometer (Thermo, USA). UV\u0026ndash;vis absorption spectra were conducted on spectrophotometer (UV-3600, Japan).\u003c/p\u003e\n\u003ch3\u003ePreparation of RuMOFNSs\u003c/h3\u003e\n\u003cp\u003eWe synthesized RuMOFNSs according to the reported method [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e], and the synthesis steps are shown in Scheme \u003cspan refid=\"Sch1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA. In a 100 mL round flask, Zn(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e\u0026middot;6H\u003csub\u003e2\u003c/sub\u003eO (18 mg), Ru(dcbpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e (18 mg), pyrazine (3.2 mg) and PVP (40 mg) were added to 64 mL of H\u003csub\u003e2\u003c/sub\u003eO. After sonicating for 10 min, the flask was heated at 80 ℃ for 24 h. The resulting precipitate was centrifuged (12000 rpm, 10 min) and thoroughly washed with water for three times. RuMOFNSs was obtained by drying at 60 ℃ for 8 h.\u003c/p\u003e \u003cp\u003eThe newly prepared RuMOFNSs (5 mg) was dispersed into 5 mL H\u003csub\u003e2\u003c/sub\u003eO and sonicated for 10 min. Then, 1 mL of EDC (400 mM)/NHS (100 mM) mixture were added and maintained for 2 h under the gently stirring. The activated RuMOFNSs were collected by centrifugal washing and redispersed into water.\u003c/p\u003e\n\u003ch3\u003ePreparation of AuNCs\u003c/h3\u003e\n\u003cp\u003eAuNCs were synthesized according to the previous research [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. As displayed in Scheme \u003cspan refid=\"Sch1\" class=\"InternalRef\"\u003e1\u003c/span\u003eB, HAuCl\u003csub\u003e4\u003c/sub\u003e solution (10 mL, 10 mM) was added into BSA (10 mL, 20 mg/mL) and kept stirring vigorously at 37\u0026deg;C. Afterward, ascorbic acid (10 \u0026micro;L, 0.35 mg/mL) was added dropwise, and pH of the solution was adjusted to 8.0 by using NaOH. After vigorous stirring for 5 h, the obtained AuNCs were purified by the dialysis (molecular weight cutoff of 2000 Da) and stored at 4\u0026deg;C for further use.\u003c/p\u003e \u003cp\u003eThe Apt (12 \u0026micro;L, 100 \u0026micro;M) was incubated with AuNCs (588 \u0026micro;L) and kept at 37\u0026deg;C for 12 h to obtain AuNCs labeled Apt (AuNCs-Apt).\u003c/p\u003e\n\u003ch3\u003eFabrication of the dual-mode aptasensor\u003c/h3\u003e\n\u003cp\u003eThe ECL sensor assembly is shown in Scheme \u003cspan refid=\"Sch1\" class=\"InternalRef\"\u003e1\u003c/span\u003eC. Firstly, 5 \u0026micro;L of activated RuMOFNSs (0.4 mg/mL) was dropped on the GCE electrode, then, 5 \u0026micro;L cDNA(2 \u0026micro;M) was coated on the RuMOFNSs modified electrode and dried in the air. After blocking with BSA, 5 \u0026micro;L of AuNCs-Apt was assembled onto the modified electrode and maintained at 37\u0026deg;C for 40 min. Thereafter, the above modified electrode was incubated with estradiol solution (5 \u0026micro;L) and kept for 2 h at room temperature. Finally, the resulted GCE electrode was coated 5 \u0026micro;L Nafion (5%) to keep the stability of the sensor.\u003c/p\u003e \u003cp\u003eScheme \u003cspan refid=\"Sch1\" class=\"InternalRef\"\u003e1\u003c/span\u003eD shows the FL mode detection. Firstly, 20 \u0026micro;L of activated RuMOFNSs was mixed with 20 \u0026micro;L of cDNA (2 \u0026micro;M), and kept at 4\u0026deg;C for 12 h. Next, 20 \u0026micro;L of BSA was added and kept at 37\u0026deg;C for 30 min. Afterward, AuNCs-Apt was added and the reaction was carried out at 37\u0026deg;C for 50 min to complete the hybridization. Subsequently, estradiol was added and incubated at 37\u0026deg;C for 2 h. The resulting solution was stored in a refrigerator at 4\u0026deg;C.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eDual -mode measurement of estradiol\u003c/h2\u003e \u003cp\u003eThe FL spectra were recorded at an excitation wavelength of 462 nm and a slit width of 5 nm. The ECL measurement was performed by incubating the aptasensor in a pH 7.0 PBS containing 100 mM K\u003csub\u003e2\u003c/sub\u003eS\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e8\u003c/sub\u003e, and the potential steps were fixed at -1.5\u0026thinsp;~\u0026thinsp;0 V with scan rate of 0.1 V/s.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Results and discussion","content":"\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eCharacterization of the nanomaterials\u003c/h2\u003e \u003cp\u003eThe morphologies of RuMOFNSs were characterized by TEM and SEM, which displayed clear and irregular sheet\u003cb\u003e-\u003c/b\u003elike structure (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA-C), and the lateral size was 0.51 \u0026micro;m (inset in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eC). Meantime, the crystal structure of RuMOFNSs was identified by XRD (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eD), the characteristic diffraction peaks were accorded with the reported literature [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. XPS spectra were also employed to confirm the elemental composition of RuMOFNSs. As displayed in Fig. \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003eA, XPS survey spectrum of RuMOFNSs showed the characteristic peaks of C 1s, O 1s, N 1s, Ru 3p and Zn 2p elements. Particularly, the high\u003cb\u003e-\u003c/b\u003eresolution spectrum of Ru 3p (Fig. \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003eB) displayed the characteristic peaks of Ru 3p\u003csub\u003e1/2\u003c/sub\u003e (484.5 eV) and Ru 3p\u003csub\u003e3/2\u003c/sub\u003e (462.4 eV), while the Zn 2p (Fig. \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003eC) showed two peaks located at 1021.3 eV (Zn 2p\u003csub\u003e3/2\u003c/sub\u003e) and 1044.5 eV (Zn 2p\u003csub\u003e1/2\u003c/sub\u003e). The auger electron peak of Zn inserted into the Ru 3p region ascribed to the co -existing of Ru and Zn elements. The synthesis of RuMOFNSs was further confirmed by FT-IR spectrum (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA) and UV-vis absorption spectrum (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB). The characteristic peaks at 1429\u0026thinsp;\u003cb\u003e\u0026minus;\u003c/b\u003e\u0026thinsp;1372 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 1718\u0026thinsp;\u0026minus;\u0026thinsp;1549 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e ascribed to the antisymmetric and symmetric stretching vibration of COO\u003csup\u003e\u0026minus;\u003c/sup\u003e, respectively [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e, \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]. The RuMOFNSs exhibited two obvious peaks at 308 nm and 474 nm (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB, curve a), which are related to the π\u0026rarr;π* electron transition of bi-pyridine ring and the dπ(Ru)\u0026rarr;π* (dcbpy) metal-to-ligand charge transfer, respectively [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. Compared with the free Ru(dcbpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e ligand (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB, curve b), the absorption peaks of RuMOFNSs showed a slight red shift, which indicating the successful coordination between Zn\u003csup\u003e2+\u003c/sup\u003e and carboxylic groups of Ru(dcbpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eA exhibited the FL spectra of AuNCs, an emission peak at 439 nm and an excitation maximum of 380 nm were observed. The HRTEM image of the AuNCs demonstrated that the particle size was around 3.3 nm (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eB).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eResponse mechanisms of dual-modal readout platform\u003c/h2\u003e \u003cp\u003eAs shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA, RuMOFNSs presented maximum absorption at 478 nm (curve a), while AuNCs had an obvious fluorescence emission spectrum at approximately 439 nm (curve b). The absorption spectrum of RuMOFNSs could be well overlapped with the fluorescence emission spectrum of AuNCs, thus, an efficient FRET from Au NCs to RuMOFNSs was achieved. The fluorescence responses of this sensing platform under different conditions are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eB, the RuMOFNSs showed a weak fluorescence signal at 610 nm (curve black). However, for the mixture of RuMOFNSs, cDNA and AuNCs-Apt, FL signal at 610 nm was observed to be significantly increased (curve red), demonstrating the feasibility of FRET between AuNCs and RuMOFNSs. In contrast, when estradiol was added in the mixture of RuMOFNSs, cDNA and AuNCs-Apt, the fluorescence intensity was decreased (curve blue). The reason is that aptamer displayed higher affinity toward estradiol, resulting in the AuNCs-Apt away from RuMOFNSs, and the increased distance between RuMOFNSs and AuNCs blocked the FRET process, thus a decreased FL signal was obtained.\u003c/p\u003e \u003cp\u003eSimilarly, the ECL responses of the sensing platform under different conditions were investigated in the range of -1.5-0 V in 0.1 M PBS (pH 7.0) with 100 mM K\u003csub\u003e2\u003c/sub\u003eS\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e8\u003c/sub\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eC). The results showed that RuMOFNSs modified GCE had weak ECL signals. However, the ECL intensities increased when cDNA and Aptamer-AuNCs was successively assembled on RuMOFNSs/GCE. The ECL signal enhancing phenomenon is attributed to the ERET between AuNCs and RuMOFNSs, because the reported maximum ECL emission of AuNCs was observed at 490 nm [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e], we found that the absorption spectrum of RuMOFNSs could be well overlapped with the ECL spectrum of AuNCs, therefore the ERET from AuNC donors to RuMOFNSs acceptors could occur and an increased ECL response was obtained. The following modification of estradiol on AuNCs-Apt/BSA/cDNA/RuMOFNSs/GCE led to the decreased ECL response because of the unsuccessful ERET.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eCharacterization of the Sensing platform\u003c/h2\u003e \u003cp\u003eThe step-by-step construction process of the dual-mode biosensor was monitored by EIS and CV. As depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eA, the charge transfer resistance (Rct) value of RuMOFNSs (curve b) was lower than that of the GCE (curve a) because RuMOFNSs blocked the electron transport. With the increased modification of cDNA, BSA and AuNCs-Apt, the increase of the Rct value indicated that these materials hindered the electron transfer channel, resulting in a decrease of the electron transfer rate. In particular, the addition of estradiol led to a significant decrease in Rct value. This change indicates that the higher affinity between Apt and estradiol could release cDNA from AuNCs-Apt, leading to the recovery of the electrode\u0026rsquo;s electron transfer ability. The CV results (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eB) exhibited the same pattern as the EIS analysis, suggesting the effective construction of the dual-mode biosensor.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eECL and FL performance evaluation of dual-mode sensors\u003c/h2\u003e \u003cp\u003eIn order to accurately evaluate the sensitivity of the dual-mode sensors, the experimental conditions of ECL and FL measurements were optimized (See supplementary information Fig. S2(A-C) for details of experimental condition optimization). As depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eA and C, the ECL and FL signal values gradually decreased with increasing concentration of estradiol in the ranges of and 50 fM to100 nM and 100 pM to 10000 nM, respectively, exhibiting a good linear relationship. The correlation equations were described as follows: for ECL, Y\u0026thinsp;=\u0026thinsp;6080.03\u0026ndash;1439.67 lgC (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.996); and for FL, Y\u0026thinsp;=\u0026thinsp;3877.17\u0026ndash;459.82 lgC (R\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.997), respectively, as exhibited in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003eB and D. According to the formula L\u0026thinsp;=\u0026thinsp;3S\u003csub\u003eb\u003c/sub\u003e/k\u003csub\u003e0\u003c/sub\u003e (S\u003csub\u003eb\u003c/sub\u003e: the standard deviation; K\u003csub\u003e0\u003c/sub\u003e: slope of the calibration curve), the ECL and FL detection limits of the sensor were calculated to be 20 fM and 97 pM, respectively. Compared with the reported single-mode detection methods (Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e), this dual-mode sensor provided better detection performance including high sensitivity, low detection limit and simple operation.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eSelectivity, reproducibility and stability of the aptasensor\u003c/h2\u003e \u003cp\u003eFor selectivity, the ECL (or FL) signals were examined against the estradiol and several interfering substances, including estrone, progesterone, bisphenol A, nitrite, nitrate, sulphate, and mixture. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eA and Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eB, the estradiol (100 pM) and the mixture of estradiol and other interferents demonstrated similar signal intensity. Moreover, in comparison with the blank solution, the addition of interfering substances (10 nM) did not cause obvious ECL (or FL) signal changes, which happens to prove the good specificity of the sensor.\u003c/p\u003e \u003cp\u003eThe reproducibility of the aptamer sensor was studied. Six electrodes were measured in parallel, and the relative standard deviations (RSDs) of the final test results were 1.85% for 100 pM estradiol (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eC). The stability of ECL signal for 1 nM estradiol was recorded by 16 consecutive cycles, showing an RSD of 1.19% (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003eD). In summary, these results demonstrated the satisfactory performance of the dual-mode sensor in estradiol analysis.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003e\u003cb\u003eAnalysis of estradiol in real sample\u003c/b\u003e\u003c/h2\u003e \u003cp\u003eIn order to evaluate the practicality of the aptasensor, real lake water and milk samples were collected and used for recovery analysis. The samples were treated according to the reported work [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], after that, the samples spiked with various estradiol concentrations were detected by the fabricated ECL-FL system. Table S2 displayed the experiment results, the recoveries of lake water ranged from 99.24 to 104.52% (ECL) and 94.72 to 101.96% (FL), respectively. The recoveries of milk ranged from 95.52 to 100.94% (ECL) and 98.94 to 103.76% (FL), respectively. These findings reveal that the dual-mode platform is a suitable strategy for estradiol assay in practical application.\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn summary, a FL-ECL dual-mode aptasensor platform was constructed by successively assembling cDNA and AuNCs-Apt onto the RuMOFNCs modified electrode. RuMOFNCs exhibited excellent FL and ECL characteristics. The sensitive detection of estradiol was successfully achieved based on resonance energy transfer between AuNCs and RuMOFNCs. Furthermore, this dual-mode sensor can also be employed to detect estradiol in real samples, demonstrating a potential application in food safety fields.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor contribution\u0026nbsp;\u003c/strong\u003eWaner Hou: writing-original draft, formal analysis, data curation.\u0026nbsp;Zhimin Liu: writing-review and editing, project administration, funding acquisition.\u0026nbsp;Xuanxuan Hao: Data curation.\u0026nbsp;Xun Lei: formal analysis；Jintao Cheng: visualization, investigation.\u0026nbsp;Yaxin Li: funding acquisition, data curation.\u0026nbsp;Leqian Hu: software, formal analysis.\u0026nbsp;Peng Li: supervision, project administration.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003eThis work was financially supported by\u0026nbsp;the National Natural Science Foundation of China (No. 22305068), Natural Science Foundation of Henan (No. 222300420426) and\u0026nbsp;Fund of the Institute of Complexity Science, Henan University of Technology (No. CSKFJJ202543).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e No datasets were generated or analysed during the\u0026nbsp;current study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics\u003c/strong\u003e \u003cstrong\u003edeclarations\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interest\u003c/strong\u003e The authors declare that they have no conflict of interests.\u003c/p\u003e\n"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eEly C, Moreira IS, Bassin JP, Dezotti MWC, Mesquita DP, Costa J, Ferreira EC, Castro PML (2022) Treatment of saline wastewater amended with endocrine disruptors by aerobic granular sludge: Assessing performance and microbial community dynamics. J Environ Chem Eng 10: 107272.\u003c/li\u003e\n\u003cli\u003eHamid N, Junaid M, Pei DS (2021) Combined toxicity of endocrine-disrupting chemicals: A review. Ecotoxicol Environ Saf 215: 112136.\u003c/li\u003e\n\u003cli\u003eNohynek GJ, Borgert CJ, Dietrich D, Rozman KK (2013) Endocrine disruption: fact or urban legend? Toxicol Lett 223: 295-305.\u003c/li\u003e\n\u003cli\u003eWaring RH, Harris RM (2005) Endocrine disrupters: A human risk? Mol Cell Endocrinol 244: 2-9.\u003c/li\u003e\n\u003cli\u003eLu HZ, Xu SF (2015) Mesoporous structured estrone imprinted Fe\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@SiO\u003csub\u003e2\u003c/sub\u003e@ mSiO\u003csub\u003e2\u003c/sub\u003e for highly sensitive and selective detection of estrogens from water samples by HPLC. Talanta 144: 303-311.\u003c/li\u003e\n\u003cli\u003eTian X, Song HJ, Wang Y, Tian XM, Tang YH, Gao RX, Zhang CX (2020) Hydrophilic magnetic molecularly imprinted nanobeads for efficient enrichment and high performance liquid chromatographic detection of 17beta-estradiol in environmental water samples. Talanta 220: 121367.\u003c/li\u003e\n\u003cli\u003eSghaier RB, Net S, Ghorbel-Abid I, Bessadok S, Coz ML, Hassan-Chehimi DB, Trabelsi-Ayadi M, Tackx M, Ouddane B (2017) Simultaneous detection of 13 endocrine disrupting chemicals in water by a combination of SPE-BSTFA derivatization and GC-MS in transboundary rivers (France-Belgium). Water Air Soil Poll 228: 1-14.\u003c/li\u003e\n\u003cli\u003eJanssens G, Mangelinckx S, Courtheyn D, Pr\u0026acute;evost S, Poorter GD, Kimpe ND, Bizec BL (2013) Application of gas chromatography-mass spectrometry/ combustion/ isotope ratio mass spectrometry (GC-MS/C/IRMS) to detect the abuse of 17\u0026beta;-Estradiol in cattle. J Agr Food Chem 61: 7242-7249.\u003c/li\u003e\n\u003cli\u003eMat Zaid MH, Abdullah J, Rozi N. Rozlan AAM, Hanifah SA (2020) A sensitive impedimetric aptasensor based on carbon nanodots modified electrode for detection of 17\u0026beta;-Estradiol. Nanomaterials 10: 1346.\u003c/li\u003e\n\u003cli\u003eSupchocksoonthorn P, Alvior Sinoy MC, de Luna MDG, Paoprasert P (2021) Facile fabrication of 17\u0026beta;-estradiol electrochemical sensor using polyaniline/carbon dot-coated glassy carbon electrode with synergistically enhanced electrochemical stability. Talanta 235: 122782.\u003c/li\u003e\n\u003cli\u003eAlsager OA, Kumar S, Zhu BC, Travas-Sejdic J, McNatty KP, Hodgkiss JM (2015) Ultrasensitive colorimetric detection of 17\u0026beta;-Estradiol: the effect of shortening DNA aptamer sequences. Anal Chem 87: 4201-4209.\u003c/li\u003e\n\u003cli\u003ePu HB, Huang ZB, Sun DW, Xie XH, Zhou WB (2019) Development of a highly sensitive colorimetric method for detecting 17\u0026beta;-Estradiol based on combination of gold nanoparticles and shortening DNA aptamers. Water Air Soil Poll 230: 1-9.\u003c/li\u003e\n\u003cli\u003eMehlhorn A, Rahimi P, Joseph Y (2018) Aptamer-based biosensors for antibiotic detection: a review. Biosensors 8: 54.\u003c/li\u003e\n\u003cli\u003eSha HF, Yan B (2021) Design of a ratiometric fluorescence sensor based on metal organic frameworks and Ru(bpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e-doped silica composites for 17\u0026beta;-Estradiol detection. J Colloid Interf Sci 583: 50-57.\u003c/li\u003e\n\u003cli\u003eLiu P, Zhao MH, Zhu HJ, Zhang ML, Li X, Wang MZ, Liu BX, Pan JM, Niu XH (2022) Dual-mode fluorescence and colorimetric detection of pesticides realized by integrating stimulus-responsive luminescence with oxidase-mimetic activity into cerium-based coordination polymer nanoparticles. J Hazard Mater 423: 127077.\u003c/li\u003e\n\u003cli\u003eHu Y, Zhu L, Me XC, Liu JS, Yao ZP, Li YC (2021) Dual-mode sensing platform for electrochemiluminescence and colorimetry detection based on a closed bipolar electrode. Anal Chem 93: 12367-12373.\u003c/li\u003e\n\u003cli\u003eHe KY, Sun LP, Wang L, Li W, Hu GX, Ji XF, Zhang YM, Xu XH (2022) Engineering DNA G-quadruplex assembly for label-free detection of Ochratoxin A in colorimetric and fluorescent dual modes. J Hazard Mater 423: 126962.\u003c/li\u003e\n\u003cli\u003eMi XN, Li H, Tan R, Tu YF (2020) Dual-modular aptasensor for detection of cardiac troponin I based on mesoporous silica films by electrochemiluminescence/electrochemical impedance spectroscopy. Anal Chem 92: 14640-14647.\u003c/li\u003e\n\u003cli\u003eZhang L, Chen FZ, Sun HD, Meng RZ, Zeng QS, Wang XX, Zhou H (2022) Stimulus-responsive metal\u0026ndash;organic framework signal-reporting system for photoelectrochemical and fluorescent dual-mode detection of ATP. ACS Appl Mater Interfaces 14: 46103-46111.\u003c/li\u003e\n\u003cli\u003eHu HT, Cui HF, Yin X, Fan QQ, Shuai H, Zhang J,Liao FS, Xiong W, Jiang HD, Fan H, Liu WM, Wei GB (2024) Dual-mode fluorescence and electrochemiluminescence sensors based on Ru-MOF nanosheets for sensitive detection of apoE genes. J Mater Chem B 12: 701-709.\u003c/li\u003e\n\u003cli\u003eGuo ZH, Yang B, Zhu J, Lou SY, Hao HM, Lu WY (2024) Light-activated, dual-mode fluorescence and colorimetric detection of estradiol with high fidelity based on aptamer\u0026rsquo;s special recognition. Food Chem 436: 137702.\u003c/li\u003e\n\u003cli\u003eHou WE, Liu ZM, Hao XX, Zheng TT, Yang XP, Li YX, Hu LQ (2025) Dual-modular electrochemiluminescence/electrochemistry aptasensing platform based on Ru(dcbpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e loaded copper oxide nanospheres and Cu-Au bimetallic nanoparticles for the sensing of estradiol. Microchem J 210: 112893.\u003c/li\u003e\n\u003cli\u003eHu DD, Zhan TY, Guo ZY, Wang S, Hu YF (2021) Electrosynthesized metal-organic framework: A dual-modality readout platform for Cu (II), coenzyme A and histone acetyltransferase analysis. Sensor Actuat B: Chem 327: 128896.\u003c/li\u003e\n\u003cli\u003eYu FY, Qin LY, Zhang H, Qin LS, Fan H (2024) A novel fluorescence-electrochemiluminescence dual-mode sensing platform for high-precision BRAF gene detection. Analyst 149: 2114-2121.\u003c/li\u003e\n\u003cli\u003eYan MX, Ye J, Zhu QJ, Zhu LP, Huang JS, Yang XR (2019) Ultrasensitive immunosensor for cardiac troponin I detection based on the electrochemiluminescence of 2D Ru-MOF nanosheets. Anal Chem 91: 10156-10163.\u003c/li\u003e\n\u003cli\u003eLu ML, Huang W, Gao SZ, Zhang JL, Liang WB, Li Y, Yuan R, Xiao DR (2022) Pyrene-based hydrogen-bonded organic frameworks as new emitters with porosity-and aggregation-induced enhanced electrochemiluminescence for ultrasensitive microRNA assay. Anal Chem 94: 15832-15838.\u003c/li\u003e\n\u003cli\u003eIshito N, Nakajima K, Maegawa Y, Inagaki S, Fukuoka A (2017) Facile formation of gold nanoparticles on periodic mesoporous bipyridine-silica. Catal Today 298: 258-262.\u003c/li\u003e\n\u003cli\u003eYu YC, Lu C, Zhang MN (2015) Gold nanoclusters@Ru(bpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e-layered double hydroxide ultrathin film as a cathodic electrochemiluminescence resonance energy transfer probe. Anal Chem 87: 8026-8032.\u003c/li\u003e\n\u003cli\u003eLiao PL, Zang SH, Wu TY, Jin HJ, Wang WK, Huang JB, Tang BZ, Yan Y (2021) Generating circularly polarized luminescence from clusterization-triggered emission using solid phase molecular self-assembly. Nat Commun 12: 5496.\u003c/li\u003e\n\u003cli\u003eLi MX, Feng QM, Zhou Z, Zhao W, Xu JJ, Chen HY (2018) Plasmon-enhanced electrochemiluminescence for nucleic acid detection based on gold nanodendrites. Anal Chem 90: 1340-347.\u003c/li\u003e\n\u003cli\u003eLi Y, Zhang LB, Zhang Z, Liu Y, Chen J, Liu J, Du PY, Guo HX, Lu XQ (2021) MnO\u003csub\u003e2\u003c/sub\u003e nanospheres assisted by cysteine combined with MnO\u003csub\u003e2\u003c/sub\u003e nanosheets as a fluorescence resonance energy transfer system for \u0026ldquo;Switch-on\u0026rdquo; detection of glutathione. Anal Chem 93: 9621-9627.\u003c/li\u003e\n\u003cli\u003eZhu SM, Wang SC, Xia MM, Wang BJ, Huang Y, Zhang DX, Zhang XJ, Wang GF (2019) Intracellular imaging of glutathione with MnO\u003csub\u003e2\u003c/sub\u003e nanosheet@Ru(bpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e-UiO-66 nanocomposites. ACS Appl Mater Interfaces 11: 31693-31699.\u003c/li\u003e\n\u003cli\u003eZhan YJ, Luo F, Guo LH, Qiu B, Lin YH, Li J, Chen GN, Lin ZY (2017) Preparation of an efficient ratiometric fluorescent nanoprobe (\u003cem\u003em\u003c/em\u003e-CDs@[Ru(bpy)\u003csub\u003e3\u003c/sub\u003e]\u003csup\u003e2+\u003c/sup\u003e) for visual and specific detection of hypochlorite on site and in living cells. ACS Sens 2: 1684-1691.\u003c/li\u003e\n\u003cli\u003eFeng QM, Xu HW, Li ZB, Chen CF, Miao XM (2022) A novel \u0026ldquo;signal off-triggered on\u0026rdquo; Fo\u0026uml;rster resonance energy transfer biosensor for the ratiometric detection of pathogenic bacteria. Sensor Actuat B: Chem 372: 132598.\u003c/li\u003e\n\u003cli\u003eKent CA, Mehl BP, Ma LQ, Papanikolas JM, Meyer TJ, Lin WB (2010) Energy transfer dynamics in metal-organic frameworks. J Am Chem Soc132: 12767-12769.\u003c/li\u003e\n\u003cli\u003eZhao YW, Jiang L, Shangguang L, Mi L, Liu AR, Liu SQ (2018) Synthesis of porphyrin-based two-dimensional metal-organic framework nanodisk with small size and few layers. J Mater Chem A 6: 2828-2833.\u003c/li\u003e\n\u003cli\u003eXiao FN, Wang M, Wang FB, Xia XH (2014) Graphene-ruthenium (II) complex composites for sensitive ECL immunosensors. Small 10: 706-716.\u003c/li\u003e\n\u003cli\u003eShi L, Li XJ, Zhu WJ, Wang YG, Du B, Cao W, Wei Q, Pang XH (2017) Sandwich-type electrochemiluminescence sensor for detection of NT-proBNP by using high efficiency quench strategy of Fe\u003csub\u003e3\u003c/sub\u003eO\u003csub\u003e4\u003c/sub\u003e@ PDA toward Ru(bpy)\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e coordinated with silver oxalate. ACS Sens 2: 1774-1778.\u003c/li\u003e\n\u003cli\u003eZhao MT, Wang YX, Ma QL, Huang Y, Zhang X, Ping JF, Zhang ZC, Lu QP, Yu YF, Xu H, Zhao YL, Zhang H (2015) Ultrathin 2D metal-organic framework nanosheets. Adv Mater 27: 7372-7378.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Scheme 1","content":"\u003cp\u003eScheme 1 is available in the Supplementary Files section.\u003c/p\u003e"}],"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":"microchimica-acta","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"miac","sideBox":"Learn more about [Microchimica Acta](https://link.springer.com/journal/604)","snPcode":"604","submissionUrl":"https://submission.springernature.com/new-submission/604/3","title":"Microchimica Acta","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"RuMOFNSs, Dual-mode, Electrochemiluminescence, Fluorescence, Resonance energy transfer, Estradiol","lastPublishedDoi":"10.21203/rs.3.rs-6278066/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6278066/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eHerein, an electrochemiluminescence (ECL)-fluorescence (FL) dual-mode aptasensing system was proposed for estradiol detection. Firstly, ruthenium-based metal\u0026ndash;organic framework nanosheets (RuMOFNSs) were synthesized by a simple one\u003cb\u003e-\u003c/b\u003epot method. RuMOFNSs exhibited both fluorescence (FL) and electrochemiluminescence (ECL) characteristics. After RuMOFNSs were immobilized on the electrode, complementary target DNA (cDNA), gold nanoclusters labeled aptamer (AuNCs-Apt) were successively assembled on the electrode to fabricate the aptasensor. The absorption spectrum of RuMOFNSs could be well overlapped with the fluorescence emission spectrum (or ECL spectrum) of AuNCs. When estradiol was absent, AuNCs-Apt could hybridize with cDNA to form double-stranded DNA, the close proximity between AuNCs and RuMOFNSs led to the efficient resonance energy transfer (RET) from AuNCs (donor) to RuMOFNSs (acceptor), thus the enhanced ECL (or FL) signals was achieved. In the presence of estradiol, the high affinity between Apt and estradiol led to the dissociation of double-stranded DNA, and the increased distance between AuNCs and RuMOFNSs hindered the RET, and the decreased ECL (or FL) signals were obtained. The aptasensor demonstrates exceptional sensitivity for detecting estradiol, with FL and ECL detection limits of 97 pM and 20 fM, respectively. This innovative approach offers significant potential for endocrine-disrupting chemical analysis.\u003c/p\u003e","manuscriptTitle":"Dual-mode electrochemiluminescence and fluorescence aptasensing platform based on resonance energy transfer for sensitive detection of estradiol","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-16 17:32:15","doi":"10.21203/rs.3.rs-6278066/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-04-13T20:46:58+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-08T19:16:18+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-06T10:13:35+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"178503591360016840786023313088206128934","date":"2025-03-28T04:43:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"24967379004592013740223642151479084314","date":"2025-03-28T02:17:47+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-03-27T16:56:57+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-03-26T01:33:04+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-03-26T01:31:29+00:00","index":"","fulltext":""},{"type":"submitted","content":"Microchimica Acta","date":"2025-03-21T13:24:03+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"microchimica-acta","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"miac","sideBox":"Learn more about [Microchimica Acta](https://link.springer.com/journal/604)","snPcode":"604","submissionUrl":"https://submission.springernature.com/new-submission/604/3","title":"Microchimica Acta","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"12c13273-9b46-4294-8db2-a3d909ee6799","owner":[],"postedDate":"April 16th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-05-26T16:10:02+00:00","versionOfRecord":{"articleIdentity":"rs-6278066","link":"https://doi.org/10.1007/s00604-025-07205-x","journal":{"identity":"microchimica-acta","isVorOnly":false,"title":"Microchimica Acta"},"publishedOn":"2025-05-23 15:58:07","publishedOnDateReadable":"May 23rd, 2025"},"versionCreatedAt":"2025-04-16 17:32:15","video":"","vorDoi":"10.1007/s00604-025-07205-x","vorDoiUrl":"https://doi.org/10.1007/s00604-025-07205-x","workflowStages":[]},"version":"v1","identity":"rs-6278066","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6278066","identity":"rs-6278066","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}