A surface-imprinting lanthanide fluorescent hybrid probe on the SiO2 microspheres for the detection of the enrofloxacin

A surface-imprinting lanthanide fluorescent hybrid probe on the SiO2 microspheres for the detection of the enrofloxacin | 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 A surface-imprinting lanthanide fluorescent hybrid probe on the SiO2 microspheres for the detection of the enrofloxacin xiaoqing huang, maoyu wang, xiaochen wang, xin shi, ruiwen li, and 2 more This is a preprint; it has not been peer reviewed by a journal.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-6545537/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 29 Jul, 2025 Read the published version in Microchimica Acta → Version 1 posted 12 You are reading this latest preprint version Abstract Enrofloxacin (ENFX), being an antibiotic of notable distinction, serves as a specialized therapeutic agent for the mitigation of animal afflictions. However, the potential ingestion of enrofloxacin through the consumption of animal-derived sustenance can give rise to a multitude of concerns such as toxicity, drug resistance, and allergic reactions. Therefore, it becomes imperative to embrace measures that expedite the quantification of enrofloxacin levels, ensuring timely detection and assessment. Herein, a surface-imprinted polymer SiO 2 @Eu(DBM) 3 phen/SMIP was synthesized using ENFX as a template molecule, methacrylic acid as a functional monomer, and Tris(dibenzoyl methane)(1,10-phenanthroline)europium(III) as a fluorescent moiety. SiO 2 @Eu(DBM) 3 phen/SMIP performs high selectivity and the low detection limit toward enrofloxacin. The specificity assay revealed its remarkable selectivity for four other fluoroquinolone antibiotics, while the rare-earth complexes displayed exceptional chemical stability, showing no significant interference from metal ions or reactive oxygen species. The results indicate that it is feasible to use SiO 2 @Eu(DBM) 3 phen/SMIP for the detection of ENFX as well as effective adsorption. This study investigates the self-assembly of rare-earth complexes on silica using suggestive blotting technique, which provides a new solution for the subsequent development of surface blotting technique. Lanthanide complexes surface imprinting Enrofloxacin detection SiO2 Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 1. Introduction Enrofloxacin (ENFX), a fluoroquinolone (FQ) antimicrobial agent, is employed in the treatment of veterinary ailments. The consumption of animals as sustenance by humans inadvertently introduces a certain quantity of antibiotics into the human body, thereby posing a potential risk to human well-being [ 1 ] . Conversely, when FQ infiltrates an organism, a substantial portion of the antibiotics administered to the animal is not metabolized by its body, but rather excreted by means of feces and urine [ 2 – 4 ] . This outcome leads to the substantial transfer of antibiotics to groundwater and even to the potable water supply [ 5 , 6 ] . Given these circumstances, the development and implementation of highly sensitive FQ-specific assays in agricultural by-products [ 7 , 8 ] , aquatic environments [ 9 , 10 ] , and animals [ 11 , 12 ] becomes imperative. Molecular Imprinting Technology (MIT), which originated in 1931, is a diagnostic approach that operates based on the selective binding interaction between an antigen and its corresponding antibody. In 1972, Wulff achieved a significant breakthrough by successfully synthesizing molecularly imprinted organic polymers using a covalent methodology. This landmark achievement opened up new avenues for the advancement of molecular imprinting technology [ 13 ] . In recent years, gas chromatography (GC) [ 14 , 15 ] and high-performance liquid chromatography (HPLC) [ 16 ] have demonstrated remarkable efficacy in the detection of contaminants, including antibiotics [ 17 ] . Nevertheless, these methods possess certain limitations that necessitate refinement, such as their high cost, the requirement for extensive training of personnel, and susceptibility to environmental factors [ 18 ] . Consequently, under specific conditions, the advantages offered by molecular imprinting, such as heightened stability [ 19 ] , enhanced sensitivity, low detection limits, and specificity [ 20 ] , can supplant the conventional assays. The emergence of Surface molecular imprinting technology (SMIT) has alleviated the inherent drawbacks of traditional free radical polymerization, which hitherto hindered the accessibility of specific binding sites within the polymer for the target analyte [ 21 – 23 ] . As a luminescent material, lanthanide elements are employed in molecular imprinting technology. This technique leverages the principles of fluorescence resonance energy transfer effect (FRET) [ 24 ] , as well as internal filtering effect (IFE) [ 25 , 26 ] , to elicit a fluorescence burst or intensification phenomenon upon interaction between the rare earth element and the targeted analyte. This enables the qualitative and quantitative assessment of pollutants. However, due to the predominantly 4f-4f transitions of lanthanide ions, their absorption coefficients are exceedingly small [ 27 ] . Relying solely on the absorption of their own energy by lanthanide ions significantly diminishes their utilization, resulting in feeble fluorescence intensity, thereby hindering the practical application of on-site detection [ 28 ] . To overcome this challenge, Weissman et al. discovered that by amalgamating rare earth elements with organic complexes, organic ligands containing conjugated double bonds undergo π → π* transitions. By effectively coupling these organic ligands with lanthanide ions, the issue of forbidden transitions in lanthanides can be efficaciously resolved [ 29 ] . Moreover, the introduction of SiO 2 , a silicon-based material, enhances the mechanical properties [ 30 ] ,photostability, thermal stability [ 31 ] ,and self-bursting phenomenon of the rare-earth complexes, addressing concerns related to concentration [ 32 , 33 ] . Therefore, a method to obtain fluorescent microspheres with a size of about 200 nanometers by seed growth and high temperature calcination has been proposed in this paper. It is worth noting that KH-570 can undergo radical polymerization with EGDMA, MAA, AIBN and template ENFX after the surface modification. Notably, molecularly imprinted microspheres with specific recognition sites were obtained by elution, centrifugation and grinding processes. Herein, this work avoids the limitations of traditional imprinting technology effectively by using lanthanide complex as substrate and giving priority to surface imprinting technology. Thus, it provides a novel direction for the application of molecular imprinting techniques in the detection of antibiotics in marine food and high-purity alcohol products. 2. Experimental Section 2.1 Reagents and materials 1,10-Phenanthroline (Phen),1,3-Diphenyl-1,3-propanedione(DBM),Tetraacetylor thosilicate(TEOS),Sodium Hydroxide(NaOH),Europium(III) Chloride Hexahydrate (EuCl 3 ·6H 2 O),Dichloromethane, Acetone Alcohol, Cetyltrimethylammonium Bromide (CTAB), Acetonitrile,3-Me-thacryloxypropyltrimet-hoxysilane(KH-570),Methacrylic Acid(MAA), Ethylene Dimethacrylate (EGDMA) and 2,2-Azobis (2-Methylpropionitrile) (AIBN) were purchased from TCI Development Co., Ltd. (Shanghai,China).Enrofloxacin(ENFX),Ciprofloxacin(CIP),Pefloxacin(PEF),Levofloxacin(OFLX),Lomefloxacin Hydrochloride(LOM) and Sparfloxacin(SPFX) were purchased from Aladdin Chemical Regent Co., Ltd.(Shanghai, China). All chemical reagents procured were of analytical grade and could be employed in experiments without requiring further purification. Fluorescence spectra were acquired employing an RF-6000 spectrophotometer (Shimadzu, Japan). Ultraviolet-visible (UV-vis) absorption spectra were recorded on a UV-2600i instrument (Shimadzu, Japan). Fourier infrared (FT-IR) spectra were determined using the SPE CTRUM100 apparatus (Perkin Elmer, USA). The elemental compositionof the fluorescent probe SiO 2 @Eu(DBM) 3 phen/SMIP was characterized using a Thermo Scientific K-Alpha model X-ray photoelectron spectrometer (with an aluminum target, Thermo Fisher Scientific, USA). The morphology of the prepared samples was examined via scanning electron microscopy (SEM). The crystalline phases were analyzed using a D8 ADVANCE model X-ray diffraction instrument (Bruker, USA). The experimental procedures were conducted employing an HF-8 multi-position magnetic stirrer, KSL-1700X muffle furnace, DHG-9030A drying oven, DZF-6000 vacuum drying oven, and TG16.5 high-speed centrifuge. 2.2 Synthesis of Eu(DBM) 3 Phen Dibenzoyl methane (DBM, 2.21 g, 9.8 mmol), Phenanthroline (Phen, 0.593 g, 3.29 mmol), and Sodium Hydroxide (NaOH, 0.4 g, 9.88 mmol) were dissolved in 50 mL of ethanol and vigorously stirred in a water bath at 500 rpm, maintaining a temperature of 60 ℃ for a duration of 2 hours. The resulting product was recorded as Solution A. Europium chloride hexahydrate (EuCl 3 ·6H 2 O, 1.205 g, 3.29 mmol) was dissolved in 10 mL of deionized water and gently stirred at 300 rpm for 10 minutes. Following the stirring, Solution A was carefully titrated with the EuCl 3 solution. As the drop-wise addition proceeded, a gradual formation of a yellow precipitate was observed within the solution, which was denoted as Solution B. To eliminate the presence of the upper layer of white suspended impurities, 70 mL of dichloromethane was introduced into Solution B. Subsequently, the resulting mixture was subjected to gentle drying at a temperature of 60 ℃ under vacuum conditions for a period of 48 hours. Finally, the yellow powder of Europium (dibenzoyl methane) 3 Phenanthroline (Eu(DBM) 3 Phen) was obtained through grinding. 2.3 Preparation of SiO 2 @Eu(DBM) 3 Phen The synthesis procedure of SiO 2 @Eu(DBM) 3 phen/SMIP was accomplished as follows: [ 34 ] Initially, a solution of 4 mL (17.8 mmol) of tetraethyl orthosilicate (TEOS) was meticulously dripped into a homogeneous emulsion comprising 60 mL of ethanol, 30 mL of deionized water, and 6 mL of ammonia. This emulsion was subjected to vigorous stirring at 600 rpm for a duration of 30 minutes. In parallel, a separate mixture of 16 mL of anhydrous ethanol, 7 mL of water, and 2 mL of ammonia was stirred at the same speed for 15 minutes. This second mixture was then added gradually to the aforementioned solution, resulting in the formation of a composite mixture designated as Solution A. Subsequently, a mixture consisting of 0.482 g (0.48 mmol) of Eu(DBM) 3 Phen, 1.1 mL (6.47 mmol) of TEOS, 0.16 g (0.439 mmol) of cetyltrimethylammonium bromide (CTAB), and 40 mL of acetone was prepared. This mixture was subjected to stirring at 600 rpm for 30 minutes. The resultant mixture was then meticulously added dropwise to Solution A while maintaining vigorous stirring at 600 rpm for an additional duration of 30 minutes. To ensure the completion of the synthesis, an additional 4 mL of TEOS was introduced into the reaction mixture, which was further stirred at 600 rpm for a prolonged period of 5 hours. Once the reaction was deemed complete, the product was separated via centrifugation, followed by a series of five ethanol washings to eliminate residual precursors and impurities. Subsequently, the product was subjected to a vacuum drying process in an oven set at 60 ℃ for a period of 24 hours. In the final step, the dried powder was transferred to a muffle furnace and subjected to a controlled heating process. The temperature was gradually increased to 200 ℃ at a heating rate of 5 ℃/min, and the resulting temperature was held for a duration of 3 hours. The final product SiO 2 @Eu(DBM) 3 Phen was obtained and then dissolved meticulously in acetonitrile. Employ sonication for a duration of 10 minutes, ensuring the complete dispersion of the powdered material within the acetonitrile solution. Subsequently, introduce 5 milliliters of water, 6 milliliters of ammonia, and 3 milliliters of KH-570 into the solution. This amalgamation is then transferred into an oil bath, cautiously set at an elevated temperature of 80 degrees Celsius, and subjected to condensation and reflux at a speed of 400 revolutions per minute for a period of 12 hours. Once the reaction concludes, perform centrifugation at a rapidity of 8000 revolutions per minute for a duration of 5 minutes. The resulting mixture is then washed thrice with ethanol and subsequently placed within a vacuum drying oven, employing a temperature of 40 degrees Celsius, for a time span of 12 hours, facilitating the desiccation process. Finally, the desired product is achieved. 2.4 Synthesis of SiO 2 @Eu(DBM) 3 phen/SMIP 0.1 g of KH-570 modified silica microspheres are carefully weighed and dissolved in 50 mL of acetonitrile. The resulting mixture is then subjected to sonication for 1 hour, ensuring complete dispersion of the powder in the solvent. Following this, 60 µL of methacrylic acid (MAA) and 70 mg of enrofloxacin are added to the solution, which is then allowed to undergo pre-polymerization for a period of 2 hours. Once the pre-polymerization reaction is concluded, 40 mg of azobisisobutyronitrile (AIBN) and 285 µL of ethylene glycol dimethacrylate (EGDMA) are introduced into the system. The ensuing reaction occurs under the condition of heating in an oil bath at 60 ℃ for a total of 18 hours. The resulting product is subsequently subjected to centrifugation and elution with a mixture of methanol and acetic acid in an 8:2 (v/v) ratio. This process is repeated until the enrofloxacin template imprinted on the molecularly imprinted polymer (MIP) is completely eluted. The purified product is then transferred to a vacuum drying oven set at 60 ℃ for a duration of 12 hours. The procedure for the non-imprinted polymer (NIP) is identical to that of the MIP, with the exception that no template molecule is added. (Scheme.1) 3. Results and discussion 3.1 The structure and morphology characterization The X-ray diffraction (XRD) patterns of SiO 2 , Eu(DBM) 3 Phen complexes, and samples subjected to calcination at elevated temperatures were meticulously examined. (Fig. 1 ) The result reveals that the XRD pattern of pure SiO 2 exhibits an amorphous structure, displaying amorphous peaks at approximately 2θ = 24°, indicating an amorphous SiO 2 morphology. In Fig. 1 b, the XRD pattern of Eu(DBM) 3 Phen showcases a lack of prominent sharp peaks, but rather exhibits weak intensity and broader amorphous peaks at 2θ = 10°, 20°, and 27°. These observations correspond to the characteristic crystalline peaks of the Eu(DBM) 3 Phen rare-earth complex, thereby affirming the successful synthesis of the Eu(DBM) 3 Phen rare-earth complex. Upon the addition of SiO 2 and subsequent calcination at 200 ℃, Fig. 1 a exhibits the emergence of characteristic peaks corresponding to the Eu(DBM) 3 Phen rare-earth complexes at 2θ = 8° and 8.7°. This signifies that the incorporation of SiO 2 and the resulting calcined composites possess enhanced stability and crystallinity in comparison to the pristine Eu(DBM) 3 Phen rare-earth complexes. Furthermore, it is noteworthy that the SiO 2 amorphous peak remains detectable at 2θ = 24°, affirming the successful binding between the rare-earth complexes and SiO 2 . The infrared spectra of SiO 2 @Eu(DBM) 3 Phen,SiO 2 @Eu(DBM) 3 Phen/SMIP and SiO 2 @Eu(DBM) 3 Phen/SNIP were analyzed to gain insights into their respective profiles. As given in Figure.2 (a), it can be clearly seen that the characteristic Si-OH absorption peak at 3428 cm -1 , indicating the presence of SiO 2 .The absorbed peaks at 1095 cm -1 and 789 cm -1 correspond to asymmetric and symmetric stretching vibrations of Si-O-Si, respectively, further confirming the successful formation of SiO 2 . Additionally, a peak at 464 cm -1 corresponds to the symmetric telescopic vibrational peaks of Si-O-Si, further supporting the presence of SiO 2 . The characteristic absorption peak of Phen in rare earth complexes, represented by the C = N peak at 1381 cm -1 , provides evidence of the successful preparation and effective combination of rare-earth complexes with SiO 2 . Furthermore, a slight fluctuation peak at 2918 cm -1 indicates that CTAB, a surfactant, has been almost eliminated through calcination. The successful modification of SiO 2 @Eu(DBM) 3 Phen by KH-570 is also evidenced by the appearance of a characteristic C = C stretching vibration peak at 1631 cm -1 .The increase in the peak at 1384 cm -1 suggests the presence of a C-H bending vibration peak in MAA (methacrylic acid). The original C = C characteristic peak at 1631 cm -1 undergoes a shift to 1628 cm -1 , accompanied by a significant increase in intensity. This shift indicates that after the initial C = C modification, the C = C in MAA masks the original peak, resulting in its intensified appearance. Another peak emerges at 1589.1 cm -1 , corresponding to the -COOH- characteristic absorption peak in the MAA structure. This peak signifies the binding of MAA to the surface of the microsphere. The simultaneous increase in these two peaks suggests the successful polymerization of the imprinted layer. (Figure.2b and Figure.2c) In order to study the element composition of the sample, the as-prepared SiO 2 @Eu(DBM) 3 Phen/SMIP were analyzed by X-ray photoelectron spectroscopy (XPS) and the results are shown in Figure.S1. Figure.S1 (a) presents the comprehensive XPS spectrum of SiO 2 @Eu(DBM) 3 Phen/SMIP, revealing the presence of five elements, namely O, C, Si, N, and Eu. Figure S1 (b) focuses on a narrow scan of C1s, wherein the peaks at 288.4 eV, 286.2 eV, and 284.4 eV correspond to C = O, C-O, and C = C/C-C functional groups, respectively. This observation confirms the successful modification of KH-570 and the polymerization of MAA. In Figure S2(a), it showcases four peaks at 1164 eV, 1154 eV, 1134.7 eV, and 1125 eV, which correspond to Eu3d 3/2 , Eu3d 3 , Eu3d 5/2 , and Eu3d 5 , respectively. These peaks are attributed to the effects of rare-earth compatibilities on the SiO 2 combination, leading to alterations in the structure of excited state energy levels. This, in turn, corresponds to adjustments in excitation wavelengths and changes in electronic leaps during fluorescence detection. Figure S2(b) focuses on the narrow scan of N1s, revealing two peaks at 399.2 eV and 402.48 eV, which can be assigned to C-N-C and N-H, respectively. The primary source of nitrogen (N) is the ENFX template, and the lower peak suggests the effective elution of ENFX from the probe. The appearance of the N-H peak is mainly attributed to the formation of hydrogen bonding between the functional monomers and the template. Figure S3(a) exhibits a secondary occurrence of C = O at 532.3 eV and 532.6 eV, corresponding to C = O and C-OH/O-C-O, respectively. This result implies that the C = O contributions originate from two different substances, indicating the successful grafting of both the KH-570 modification and free radical polymerization onto the surface of the fluorescent microspheres. Finally, Figure S3(b) focuses on a narrow scan of Si2p, which reveals the presence of two peaks at 102.98 eV and 101.78 eV corresponding to Si-O and Si-C, respectively. These findings all confirm the existence of SiO 2 and provide further support for the success of the KH-570 modification, aligning with the C = C plot observed in the FT-IR spectrum., respectively, confirming the presence of SiO 2 as well as corroborating the success of the KH-570 modification, which corresponds to the C = C plot in the FT-IR spectrum. 3.2 Fluorescence properties The morphology of the as-obtained samples was investigated by SEM.(Figure.3) Notably, the calcinated SiO 2 @Eu(DBM) 3 Phen microspheres(b) exhibit an average particle size of approximately 200 nm, boasting a smooth surface. However, it is worth mentioning that some of the fluorescent microspheres showcase partial aggregation, a phenomenon which can be ascribed to the relatively low incorporation of CTAB as a soft template, resulting in a certain degree of agglomeration. In comparison to the morphology of SiO 2 @Eu(DBM) 3 Phen fluorescent microspheres depicted in Fig. 3 (a), the surface of SiO 2 @Eu(DBM) 3 Phen/SMIP unveils a uniform molecularly imprinted layer of enrofloxacin. Because of the crosslinker initiating the free radical polymerization reaction, the agglomeration phenomenon induced by the addition of CTAB becomes more pronounced. A specified quantity of the product SiO 2 @Eu(DBM) 3 Phen/SMIP was dissolved in ethanol. After subjecting it to ultrasonic dispersion, 3 mL of the well-dispersed solution was taken and combined with varying concentrations of enrofloxacin. The mixture was then incubated for a duration of 10 minutes at room temperature, during which the fluorescence intensity of each solution was recorded. The fluorescence measurements were conducted under specific conditions: excitation at a wavelength of 278 nm, a slit width of 5 nm, and a scanning speed of 2000 nm/min. Upon the examination of pure complex Eu(DBM) 3 Phen, the emission spectrum exhibits a series of 5 D 0 → 7 F 2 (J = 0,1,2,3,4) (579,591,614,651,699 nm) transitions of Eu 3+ . Notably, the most intense emission peak corresponds to the aforementioned 5 D 0 → 7 F 2 leaps, aligning with the documented electronic transitions of Eu(DBM) 3 Phen in the literature [ 34 , 35 ] . This compelling evidence confirms the successful preparation of the rare-earth complex Eu(DBM) 3 Phen.Furthermore, Fig S4 reveals a distinct blue shift in the excitation wavelength, shifting from the pure rare earth coordination excitation wavelength of 306 nm to 280 nm for SiO 2 @Eu(DBM) 3 Phen/SMIP. This phenomenon can primarily be attributed to the incorporation of the silica matrix, which induces modifications in the surrounding environment of the rare earths, consequently influencing the electronic transitions7. Moreover, the interactions between 5 D 0 → 7 F 1 and 5 D 0 → 7 F 3 transitions, as well as the observed enhancement of 5 D 0 → 7 F 4 peaks and the reduction of 5 D 0 → 7 F 0 transitions, can be attributed to the energetic interaction between these transitions, ultimately leading to an increase in the excited state electronic energy level of the system. These findings robustly support the notion of a favorable binding morphology between SiO 2 and the rare earth complexes. To optimize the assay for burst rate, two parameters, namely probe concentration and incubation time, were meticulously evaluated. It is important to note that excessively high probe concentration or insufficient incubation time could lead to a low quenching rate, rendering the detection experiments unsuitable for the substance under investigation. Hence, in this study, we explored the optimal detection system probe concentration by varying the concentration of SiO 2 @Eu(DBM) 3 Phen/SMIP from 0.1 mg/mL to 0.6 mg/mL and measuring its effect on the detection of ENFX at a concentration of 100 µM. Figure S5(b) illustrates that a low probe concentration leads to a significant fluorescence burst upon addition of ENFX, which gradually decreases as the concentration of the former increases beyond 0.3 mg/ml. Therefore, taking into consideration both the fluorescence intensity and burst rate, a fluorescent probe concentration of 0.35 mg/ml was deemed optimal. Furthermore, the incubation time was identified as another crucial factor influencing the fluorescent probe. Figure S5(a) provides evidence that the fluorescence burst rate tends to stabilize after an incubation time of 8 minutes. Hence, for subsequent fluorescence performance testing experiments, the incubation time was fixed at 8 minutes, and the concentration of the probe was maintained at 0.35 mg/ml. 3.3 Sensing detection performance of the fluorescent probe To investigate the specific recognition and detection capabilities of the SiO 2 @Eu(DBM) 3 Phen/SMIP probe towards ENFX, four fluoroquinolone antibiotics, namely Lomefloxacin Hydrochlorde (LOM), Sparfloxasin (SPFX), Levofloxacin (OFLX), and Ciprofloxacin (CIP), were selected for comparation, all the structures were illustrated in Fig. 4 (b). Furthermore, the structures of MIP and NIP were utilized for the burst (F 0 /F) experiments with the concentration of 200 µM. From Fig. 4 (a), it is evident that both MIP and NIP exhibit a certain degree of bursting upon exposure to fluoroquinolone antibiotics, with comparable levels of intensity. However, the bursting effect of MIP on ENFX was notably stronger when compared to the other antibiotics of identical structure. This enhanced effect can be attributed to the presence of specific binding sites for ENFX within the molecular imprinting layer, leading to the selective recognition of ENFX by SiO 2 @Eu(DBM) 3 Phen/SMIP. These findings affirm that the superior specific recognition and detection performance of SiO 2 @Eu(DBM) 3 Phen /SMIP for ENFX. To assess the sensitivity of the fluorescence response of SiO 2 @Eu(DBM) 3 Phen/SMIP, a series of ENFX standard solutions with varying concentrations (20 ~ 100 µM) were prepared and added to the SiO 2 @Eu(DBM) 3 Phen/SMIP solution. The fluorescence intensity values were measured before and after mixing, following 8 minutes interaction between the two. As depicted in Fig. 5 (a), the intensity of the molecularly imprinted fluorescent probe exhibited a significant decrease in the range of 100 ~ 70 µM with the gradual increase of ENFX concentration. The fluorescence burst effect tended to level off as the concentration of the detector was reduced to 30 µM. A good linear relationship between the fluorescence burst rate (F 0 /F) of SiO 2 @Eu(DBM) 3 Phen/SMIP and the concentration of ENFX in the range of 20 ~ 100 µM was observed, as illustrated in Fig. 5 (b). The fluorescence quenching constant of Stern-Volmer, K sv , was determined using the equation \(\:\text{F}\text{0}⁄\text{F}=\text{K}\text{sv}\left[\text{C}\right]+1\) , where F 0 is the fluorescence intensity of the molecularly imprinted probe before the addition of ENFX, and F is the fluorescence intensity after the addition of different concentrations of ENFX. C represents the concentration of added ENFX. This was fitted to obtain the linear regression equation: \(\:\text{F}\text{0}/\text{F}=0.00271\text{C}\text{e}\text{n}\text{r}+1.11764\) , with an R 2 value of 0.99225, and a fluorescence quenching constant of 0.00271. Based on the standard deviation of the blank signal obtained from five consecutive detections, δ, and the slope of the linear equation, S, the limit of detection (LOD) was calculated as LOD=3.07 µM. The LOD could be further improved to 1.5 µM within the range of 20~100 µM, based on the linear relationship between the fluorescence quenching rate and the concentration of added ENFX for SiO 2 @Eu(DBM) 3 Phen/SMIP. In addition, the blotting effect was examined by investigating the fluorescence detection performance of SiO 2 @Eu(DBM) 3 Phen/SNIP under the same assay conditions. The linear regression equation \(\:\text{F}\text{0}\text{/F=0.00224Cenr+0.00157}\) , with an R 2 value of 0.9758, and a fluorescence burst constant of K sv (NIP)=0.00224 were derived using the Stern-Volmer equation. The imprinting factor, IF, was calculated according to the formula IF=K sv (MIP)/K sv (NIP), yielding a value of 1.2098. These results demonstrate the superior sensitivity and specificity of SiO 2 @Eu(DBM) 3 Phen/SMIP as a molecular fluorescence probe for the detection of ENFX. Moreover, we have undertaken experiments to assess the impact of individual metal ions and acid radical ions on the efficacy of molecularly imprinted probes in mitigating interference. The selectivity of the SiO 2 @Eu(DBM) 3 Phen/SMIP sensor for ENFX was explored by selecting the different ions including Cu 2+ , Na + , Mn 2+ , Ni 2+ , K + , Co 2+ , Cl - , and SO 4 2- .(Fig. S8) As a result, all these ions did not exert any discernible effect on the fluorescence emission of SiO 2 @Eu(DBM) 3 Phen/SMIP. This suggests that the detection of ENFX by SiO 2 @Eu(DBM) 3 Phen/SMIP may remain unaffected by fluoroquinolone homologs antibiotics and diverse metal ions. These results unequivocally demonstrate that SiO 2 @Eu(DBM) 3 Phen/SMIP exhibits exceptional specific recognition ability, detection performance, and resilience against interference in the detection of ENFX. 3.4 Adsorption properties of the probe SiO 2 @Eu(DBM) 3 Phen/SMIP To investigate the adsorption rate of the SiO 2 @Eu(DBM) 3 Phen/SMIP fluorescent probe on the target ENFX and ascertain the presence of specific binding sites, the adsorption capacities of MIP and NIP on ENFX were measured at various times, as depicted in Fig S6. The adsorption equilibrium time for SiO 2 @Eu(DBM) 3 Phen/SMIP was found to be 30 minutes, with an adsorption capacity of 1.75 mg/g. In contrast, the adsorption equilibrium time for SiO 2 @Eu(DBM) 3 Phen/SNIP was 20 minutes, with an adsorption capacity of 1.61 mg/g. This difference in adsorption capacity is attributed to the existence of specific binding sites within SiO 2 @Eu(DBM) 3 Phen/SMIP, resulting in a greater adsorption capacity for ENFX. This finding further confirms the presence of a molecularly imprinted layer with specific recognition capabilities. To further explore the adsorption capacity of SiO 2 @Eu(DBM) 3 Phen/SMIP on the target ENFX, varied concentrations of ENFX solutions were prepared for static adsorption experiments. As illustrated in Figure S7, the adsorption capacity of MIP and NIP exhibited a progressive increase with the ascending concentration of ENFX. Additionally, the adsorption capacity of MIP surpassed that of NIP, with the maximum adsorption capacity of SiO 2 @Eu(DBM) 3 Phen/SMIP (54.64 mg/g) being 1.08 times that of NIP when the concentration reached 500 mg/L. These findings suggest that the probe possesses admirable adsorption characteristics, while the presence of specific sites after the blotting elution template elevates the adsorption capacity of ENFX. 3.5 Application to the actual sample detection To evaluate the applicability and reliability of the proposed SiO 2 @Eu(DBM) 3 Phen/SMIP fluorescence system, real sample testing was conducted using milk and the drinking water to investigate the performance of the SiO 2 @Eu(DBM) 3 Phen/SMIP in practical ENFX, detection (See Table S1 ). The standard addition (recovery) method was employed to detect ENFX in the real sampls. Specifically, we have expanded the range of detection for low concentrations in actual samples, selecting 5 µM and 10 µM as the test concentrations, and obtained the results of the recovery rate through calculations involving the added standards. In the detection of actual samples, the scalar added is typically 0.5 to 2.0 times the content of the analyte. The concentration of the added standard should be high, and the volume should be controlled within a small range, usually not exceeding 1% of the volume of the original sample. If the recovery rate exceeds 100%, it may indicate that the added amount is too large or that there is an error in the measured value. The ideal range for the recovery rate is generally between 90% and 110%, with values closer to 100% indicating higher reliability of the data. According to the calculation results presented in Table S1 , the recovery rates are close to 100% within the detection range and approach 100% at low concentrations near the limit of detection. These findings confirm the applicability of this fluorescence probe for the analysis of real samples. 4. Conclusion In summary, we have successfully developed the molecularly imprinted particle generated through surface-imprinted polymerization exhibited remarkable levels of recognition specificity towards enrofloxacin. The fluorescent microspheres demonstrated strong fluorescence emission, attributed mainly to the transfer of energy from the two ligands, DBM and Phen, to the Eu 3+ ions via the antenna effect. SiO 2 is suitable as substrate for surface imprinting materials, and the combination with Eu(DBM) 3 Phen can further enhance the mechanical strength, thermal stability and fluorescence stability of fluorescent microspheres. The blotting microspheres manifested a sensitive and rapid fluorescence response to ENFX, with a low detection limit and excellent specificity. These results suggest a broad potential for the application of this technology in surface blotting and aquatic product detection. Declarations Supplementary Information Lanthanide complexes and fluorescent microsphere emission profiles for electron jumps. XPS spectra of SiO 2 @Eu(DBM) 3 Phen/SMIP and high-resolution spectra of C1s,N1s,O1s,Si2p,Eu3d.Optimization of molecular blotting concentration and incubation time experiments. Dynamic adsorption profiles of MIP/NIP to enrofloxacin. Author contributions Huang Xiaoqing and Wang Maoyu: experiments, data analysis, investigation, writing - initial draft, Li Ying's writing - comments and editing. Wang Xiaochen investigates and writes - initial draft. Shi Xin, Li Ruisi, and Wu Shuang: Data organization, analysis, and investigation. Founding This work was supported by the National Natural Science Foundation of China (21101107, 51173107), State Key Laboratory of Pollution Control and Resource Reuse Foundation, (NO. PCRRF19017) Data availability No datasets were generated or analysed during the current study Ethical approval Not applicable (this research does not involve human or animal samples). Competing interests The authors declare no competing interests. References M. Rusch, A. Spielmeyer, H. Zorn, G. 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Ghosh, Recent trends in binary and ternary rare-earth fluoride nanophosphors: How structural and physical properties influence optical behavior, Journal of Luminescence, 189 (2017) 44-63,https://https://doi.org/10.1016/j.jlumin.2017.03.062 R.K. Sharma, P. Ghosh, Lanthanide-Doped Luminescent Nanophosphors via Ionic Liquids, Front Chem, 9 (2021) 715531,https://10.3389/fchem.2021.715531 S.I. Weissman, Intramolecular Energy Transfer The Fluorescence of Complexes of Europium, The Journal of Chemical Physics, 10 (1942) 214-217,https://10.1063/1.1723709 T. Jin, S. Tsutsumi, Y. Deguchi, K.-i. Machida, G.y. Adachi, Luminescence Property of the Terbium Bipyridyl Complex Incorporated in Silica Matrix by a Sol‐Gel Method, Journal of The Electrochemical Society, 142 (1995),https://10.1149/1.2050043 D. Dong, S. Jiang, Y. Men, X. Ji, B. Jiang, Nanostructured Hybrid Organic-Inorganic Lanthanide Complex Films Produced In Situ via a Sol-Gel Approach, Advanced Materials, 12 (2000) 646-649,https://10.1002/(sici)1521-4095(200005)12:9 M.H. Gehlen, The centenary of the Stern-Volmer equation of fluorescence quenching: From the single line plot to the SV quenching map, Journal of Photochemistry and Photobiology C: Photochemistry Reviews, 42 (2020) 100338,https://https://doi.org/10.1016/j.jphotochemrev.2019.100338 S.A. Meredith, Y. Kusunoki, S.D. Connell, K. Morigaki, S.D. Evans, P.G. Adams, Self-Quenching Behavior of a Fluorescent Probe Incorporated within Lipid Membranes Explored Using Electrophoresis and Fluorescence Lifetime Imaging Microscopy, The Journal of Physical Chemistry B, 127 (2023) 1715-1727,https://10.1021/acs.jpcb.2c07652 Y. Mou, M. Kang, F. Wang, M. Liu, K. Chen, R. Sun, Synthesis and luminescent properties of monodisperse SiO 2 @SiO 2 :Eu(DBM) 3 phen microspheres with core-shell structure by sol–gel method, Journal of Sol-Gel Science and Technology, 83 (2017) 447-456,https://10.1007/s10971-017-4424-x S. Shen, M. Kang, A. Lu, K. Chen, X. Lv, L. Yuan, R. Sun, Synthesis of silica/rare-earth complex hybrid luminescence materials with cationic surfactant and their photophysical properties, Journal of Physics and Chemistry of Solids, 133 (2019) 79-84,https://10.1016/j.jpcs.2019.05.011 Scheme Scheme 1 is available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files SupportinginformationMicrochimicaActa.docx floatimage1.jpeg Scheme 1. Schematic diagram of SiO 2 @Eu(DBM) 3 Phen/MIP synthesis process Cite Share Download PDF Status: Published Journal Publication published 29 Jul, 2025 Read the published version in Microchimica Acta → Version 1 posted Editorial decision: Revision requested 17 May, 2025 Reviews received at journal 12 May, 2025 Reviews received at journal 08 May, 2025 Reviews received at journal 03 May, 2025 Reviewers agreed at journal 03 May, 2025 Reviewers agreed at journal 02 May, 2025 Reviewers agreed at journal 02 May, 2025 Reviewers agreed at journal 02 May, 2025 Reviewers invited by journal 02 May, 2025 Editor assigned by journal 30 Apr, 2025 Submission checks completed at journal 30 Apr, 2025 First submitted to journal 28 Apr, 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. 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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-6545537","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":451486399,"identity":"78bd0c18-c992-489e-86c9-f09e9ada2d6f","order_by":0,"name":"xiaoqing huang","email":"","orcid":"","institution":"University of Shanghai for Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"xiaoqing","middleName":"","lastName":"huang","suffix":""},{"id":451486400,"identity":"aca25a99-9675-4ad8-9841-d4dac309a1fc","order_by":1,"name":"maoyu wang","email":"","orcid":"","institution":"University of Shanghai for Science and 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and Technology","correspondingAuthor":true,"prefix":"","firstName":"ying","middleName":"","lastName":"li","suffix":""}],"badges":[],"createdAt":"2025-04-28 08:23:24","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6545537/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6545537/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00604-025-07369-6","type":"published","date":"2025-07-29T16:21:12+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":82182511,"identity":"a238dd60-526d-411c-87ce-57a3bccc2967","added_by":"auto","created_at":"2025-05-07 12:17:33","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":253645,"visible":true,"origin":"","legend":"\u003cp\u003e(a) XRD patterns of Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen doped core-shell SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen particles (b) XRD patterns of pure Eu complexes\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-6545537/v1/2843f2122b6460417c79cf2e.png"},{"id":82182512,"identity":"ed8edd1a-dc24-48df-a981-1099f2657cf4","added_by":"auto","created_at":"2025-05-07 12:17:33","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":90112,"visible":true,"origin":"","legend":"\u003cp\u003eFI-TR spectra of (a)SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen (b) SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP and (c) SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SNIP\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-6545537/v1/fc2eaa55b76f9a7a88bdc122.png"},{"id":82182519,"identity":"9f9b77ab-1fad-44f3-a8fa-fd721c1604ac","added_by":"auto","created_at":"2025-05-07 12:17:34","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":726280,"visible":true,"origin":"","legend":"\u003cp\u003eThe SEM images of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/MIP(a) and SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen (b)\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6545537/v1/8bfcd73e7aa0d7d382bfba6a.jpeg"},{"id":82182514,"identity":"aa1f24c6-796b-4e14-8b40-88dad5673fe8","added_by":"auto","created_at":"2025-05-07 12:17:33","extension":"jpeg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":130648,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Schematic diagram of specific detection ability analysis for enrofloxacin (ENFX), lomefloxacin hydrochloride (LOM), sparfloxacin (SPFX), levofloxacin (OFLX), ciprofloxacin (CIP)) selected (b) Chemical structure diagram of 5 fluoroquinolone antibiotics\u003c/p\u003e","description":"","filename":"floatimage5.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6545537/v1/c0fd3ce93587240817bf8fee.jpeg"},{"id":82183317,"identity":"eae699c7-dfef-42db-9dcd-6bd662418cb9","added_by":"auto","created_at":"2025-05-07 12:25:33","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":300648,"visible":true,"origin":"","legend":"\u003cp\u003ePlots of fluorescence quenching rates of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP (a) and SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SNIP (c) versus ENFX concentration; plots of fluorescence quenching rates of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP (b) and SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SNIP (d) plots of linear fit to ENFX\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-6545537/v1/d59e3b58eeeed3bc1421bbc4.png"},{"id":88268237,"identity":"e1795502-6864-40ad-9067-dbdad542ce6c","added_by":"auto","created_at":"2025-08-04 16:50:20","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2167881,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6545537/v1/a5b43e80-2f40-4e0e-966d-f1fa1f3e78a2.pdf"},{"id":82183318,"identity":"7629ad9b-c8dc-449f-b913-a3879d6595ea","added_by":"auto","created_at":"2025-05-07 12:25:34","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":1018781,"visible":true,"origin":"","legend":"","description":"","filename":"SupportinginformationMicrochimicaActa.docx","url":"https://assets-eu.researchsquare.com/files/rs-6545537/v1/cf003ce79f3f6758ed62fe41.docx"},{"id":82182510,"identity":"9961809f-2d87-40f6-be0a-ee20f85a4fbd","added_by":"auto","created_at":"2025-05-07 12:17:33","extension":"jpeg","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":211425,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eScheme 1.\u003c/strong\u003e Schematic diagram of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/MIP synthesis process\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6545537/v1/415b346ee6dda8cdfd159d79.jpeg"}],"financialInterests":"No competing interests reported.","formattedTitle":"A surface-imprinting lanthanide fluorescent hybrid probe on the SiO2 microspheres for the detection of the enrofloxacin","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eEnrofloxacin (ENFX), a fluoroquinolone (FQ) antimicrobial agent, is employed in the treatment of veterinary ailments. The consumption of animals as sustenance by humans inadvertently introduces a certain quantity of antibiotics into the human body, thereby posing a potential risk to human well-being\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. Conversely, when FQ infiltrates an organism, a substantial portion of the antibiotics administered to the animal is not metabolized by its body, but rather excreted by means of feces and urine\u003csup\u003e[\u003cspan additionalcitationids=\"CR3\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/sup\u003e. This outcome leads to the substantial transfer of antibiotics to groundwater and even to the potable water supply\u003csup\u003e[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e. Given these circumstances, the development and implementation of highly sensitive FQ-specific assays in agricultural by-products\u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e, aquatic environments\u003csup\u003e[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e, and animals\u003csup\u003e[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e becomes imperative.\u003c/p\u003e \u003cp\u003eMolecular Imprinting Technology (MIT), which originated in 1931, is a diagnostic approach that operates based on the selective binding interaction between an antigen and its corresponding antibody. In 1972, Wulff achieved a significant breakthrough by successfully synthesizing molecularly imprinted organic polymers using a covalent methodology. This landmark achievement opened up new avenues for the advancement of molecular imprinting technology\u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e. In recent years, gas chromatography (GC)\u003csup\u003e[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/sup\u003e and high-performance liquid chromatography (HPLC)\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e have demonstrated remarkable efficacy in the detection of contaminants, including antibiotics\u003csup\u003e[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/sup\u003e. Nevertheless, these methods possess certain limitations that necessitate refinement, such as their high cost, the requirement for extensive training of personnel, and susceptibility to environmental factors\u003csup\u003e[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/sup\u003e. Consequently, under specific conditions, the advantages offered by molecular imprinting, such as heightened stability\u003csup\u003e[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]\u003c/sup\u003e, enhanced sensitivity, low detection limits, and specificity\u003csup\u003e[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/sup\u003e, can supplant the conventional assays. The emergence of Surface molecular imprinting technology (SMIT) has alleviated the inherent drawbacks of traditional free radical polymerization, which hitherto hindered the accessibility of specific binding sites within the polymer for the target analyte\u003csup\u003e[\u003cspan additionalcitationids=\"CR22\" citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eAs a luminescent material, lanthanide elements are employed in molecular imprinting technology. This technique leverages the principles of fluorescence resonance energy transfer effect (FRET)\u003csup\u003e[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]\u003c/sup\u003e, as well as internal filtering effect (IFE)\u003csup\u003e[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]\u003c/sup\u003e, to elicit a fluorescence burst or intensification phenomenon upon interaction between the rare earth element and the targeted analyte. This enables the qualitative and quantitative assessment of pollutants. However, due to the predominantly 4f-4f transitions of lanthanide ions, their absorption coefficients are exceedingly small\u003csup\u003e[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]\u003c/sup\u003e. Relying solely on the absorption of their own energy by lanthanide ions significantly diminishes their utilization, resulting in feeble fluorescence intensity, thereby hindering the practical application of on-site detection\u003csup\u003e[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]\u003c/sup\u003e. To overcome this challenge, Weissman et al. discovered that by amalgamating rare earth elements with organic complexes, organic ligands containing conjugated double bonds undergo π \u0026rarr; π* transitions. By effectively coupling these organic ligands with lanthanide ions, the issue of forbidden transitions in lanthanides can be efficaciously resolved\u003csup\u003e[\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]\u003c/sup\u003e. Moreover, the introduction of SiO\u003csub\u003e2\u003c/sub\u003e, a silicon-based material, enhances the mechanical properties\u003csup\u003e[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]\u003c/sup\u003e,photostability, thermal stability\u003csup\u003e[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]\u003c/sup\u003e,and self-bursting phenomenon of the rare-earth complexes, addressing concerns related to concentration\u003csup\u003e[\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eTherefore, a method to obtain fluorescent microspheres with a size of about 200 nanometers by seed growth and high temperature calcination has been proposed in this paper. It is worth noting that KH-570 can undergo radical polymerization with EGDMA, MAA, AIBN and template ENFX after the surface modification. Notably, molecularly imprinted microspheres with specific recognition sites were obtained by elution, centrifugation and grinding processes. Herein, this work avoids the limitations of traditional imprinting technology effectively by using lanthanide complex as substrate and giving priority to surface imprinting technology. Thus, it provides a novel direction for the application of molecular imprinting techniques in the detection of antibiotics in marine food and high-purity alcohol products.\u003c/p\u003e"},{"header":"2. Experimental Section","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Reagents and materials\u003c/h2\u003e \u003cp\u003e1,10-Phenanthroline (Phen),1,3-Diphenyl-1,3-propanedione(DBM),Tetraacetylor thosilicate(TEOS),Sodium Hydroxide(NaOH),Europium(III) Chloride Hexahydrate (EuCl\u003csub\u003e3\u003c/sub\u003e\u0026middot;6H\u003csub\u003e2\u003c/sub\u003eO),Dichloromethane, Acetone Alcohol, Cetyltrimethylammonium Bromide (CTAB), Acetonitrile,3-Me-thacryloxypropyltrimet-hoxysilane(KH-570),Methacrylic Acid(MAA), Ethylene Dimethacrylate (EGDMA) and 2,2-Azobis (2-Methylpropionitrile) (AIBN) were purchased from TCI Development Co., Ltd. (Shanghai,China).Enrofloxacin(ENFX),Ciprofloxacin(CIP),Pefloxacin(PEF),Levofloxacin(OFLX),Lomefloxacin Hydrochloride(LOM) and Sparfloxacin(SPFX) were purchased from Aladdin Chemical Regent Co., Ltd.(Shanghai, China). All chemical reagents procured were of analytical grade and could be employed in experiments without requiring further purification.\u003c/p\u003e \u003cp\u003eFluorescence spectra were acquired employing an RF-6000 spectrophotometer (Shimadzu, Japan). Ultraviolet-visible (UV-vis) absorption spectra were recorded on a UV-2600i instrument (Shimadzu, Japan). Fourier infrared (FT-IR) spectra were determined using the SPE CTRUM100 apparatus (Perkin Elmer, USA). The elemental compositionof the fluorescent probe SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ephen/SMIP was characterized using a Thermo Scientific K-Alpha model X-ray photoelectron spectrometer (with an aluminum target, Thermo Fisher Scientific, USA). The morphology of the prepared samples was examined via scanning electron microscopy (SEM). The crystalline phases were analyzed using a D8 ADVANCE model X-ray diffraction instrument (Bruker, USA). The experimental procedures were conducted employing an HF-8 multi-position magnetic stirrer, KSL-1700X muffle furnace, DHG-9030A drying oven, DZF-6000 vacuum drying oven, and TG16.5 high-speed centrifuge.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Synthesis of Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen\u003c/h2\u003e \u003cp\u003eDibenzoyl methane (DBM, 2.21 g, 9.8 mmol), Phenanthroline (Phen, 0.593 g, 3.29 mmol), and Sodium Hydroxide (NaOH, 0.4 g, 9.88 mmol) were dissolved in 50 mL of ethanol and vigorously stirred in a water bath at 500 rpm, maintaining a temperature of 60 ℃ for a duration of 2 hours. The resulting product was recorded as Solution A. Europium chloride hexahydrate (EuCl\u003csub\u003e3\u003c/sub\u003e\u0026middot;6H\u003csub\u003e2\u003c/sub\u003eO, 1.205 g, 3.29 mmol) was dissolved in 10 mL of deionized water and gently stirred at 300 rpm for 10 minutes. Following the stirring, Solution A was carefully titrated with the EuCl\u003csub\u003e3\u003c/sub\u003e solution. As the drop-wise addition proceeded, a gradual formation of a yellow precipitate was observed within the solution, which was denoted as Solution B. To eliminate the presence of the upper layer of white suspended impurities, 70 mL of dichloromethane was introduced into Solution B. Subsequently, the resulting mixture was subjected to gentle drying at a temperature of 60 ℃ under vacuum conditions for a period of 48 hours. Finally, the yellow powder of Europium (dibenzoyl methane)\u003csub\u003e3\u003c/sub\u003ePhenanthroline (Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen) was obtained through grinding.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Preparation of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen\u003c/h2\u003e \u003cp\u003eThe synthesis procedure of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ephen/SMIP was accomplished as follows:\u003csup\u003e[\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]\u003c/sup\u003e Initially, a solution of 4 mL (17.8 mmol) of tetraethyl orthosilicate (TEOS) was meticulously dripped into a homogeneous emulsion comprising 60 mL of ethanol, 30 mL of deionized water, and 6 mL of ammonia. This emulsion was subjected to vigorous stirring at 600 rpm for a duration of 30 minutes. In parallel, a separate mixture of 16 mL of anhydrous ethanol, 7 mL of water, and 2 mL of ammonia was stirred at the same speed for 15 minutes. This second mixture was then added gradually to the aforementioned solution, resulting in the formation of a composite mixture designated as Solution A. Subsequently, a mixture consisting of 0.482 g (0.48 mmol) of Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen, 1.1 mL (6.47 mmol) of TEOS, 0.16 g (0.439 mmol) of cetyltrimethylammonium bromide (CTAB), and 40 mL of acetone was prepared. This mixture was subjected to stirring at 600 rpm for 30 minutes. The resultant mixture was then meticulously added dropwise to Solution A while maintaining vigorous stirring at 600 rpm for an additional duration of 30 minutes. To ensure the completion of the synthesis, an additional 4 mL of TEOS was introduced into the reaction mixture, which was further stirred at 600 rpm for a prolonged period of 5 hours. Once the reaction was deemed complete, the product was separated via centrifugation, followed by a series of five ethanol washings to eliminate residual precursors and impurities. Subsequently, the product was subjected to a vacuum drying process in an oven set at 60 ℃ for a period of 24 hours. In the final step, the dried powder was transferred to a muffle furnace and subjected to a controlled heating process. The temperature was gradually increased to 200 ℃ at a heating rate of 5 ℃/min, and the resulting temperature was held for a duration of 3 hours. The final product SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen was obtained and then dissolved meticulously in acetonitrile. Employ sonication for a duration of 10 minutes, ensuring the complete dispersion of the powdered material within the acetonitrile solution. Subsequently, introduce 5 milliliters of water, 6 milliliters of ammonia, and 3 milliliters of KH-570 into the solution. This amalgamation is then transferred into an oil bath, cautiously set at an elevated temperature of 80 degrees Celsius, and subjected to condensation and reflux at a speed of 400 revolutions per minute for a period of 12 hours. Once the reaction concludes, perform centrifugation at a rapidity of 8000 revolutions per minute for a duration of 5 minutes. The resulting mixture is then washed thrice with ethanol and subsequently placed within a vacuum drying oven, employing a temperature of 40 degrees Celsius, for a time span of 12 hours, facilitating the desiccation process. Finally, the desired product is achieved.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4 Synthesis of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ephen/SMIP\u003c/h2\u003e \u003cp\u003e0.1 g of KH-570 modified silica microspheres are carefully weighed and dissolved in 50 mL of acetonitrile. The resulting mixture is then subjected to sonication for 1 hour, ensuring complete dispersion of the powder in the solvent. Following this, 60 \u0026micro;L of methacrylic acid (MAA) and 70 mg of enrofloxacin are added to the solution, which is then allowed to undergo pre-polymerization for a period of 2 hours. Once the pre-polymerization reaction is concluded, 40 mg of azobisisobutyronitrile (AIBN) and 285 \u0026micro;L of ethylene glycol dimethacrylate (EGDMA) are introduced into the system. The ensuing reaction occurs under the condition of heating in an oil bath at 60 ℃ for a total of 18 hours. The resulting product is subsequently subjected to centrifugation and elution with a mixture of methanol and acetic acid in an 8:2 (v/v) ratio. This process is repeated until the enrofloxacin template imprinted on the molecularly imprinted polymer (MIP) is completely eluted. The purified product is then transferred to a vacuum drying oven set at 60 ℃ for a duration of 12 hours. The procedure for the non-imprinted polymer (NIP) is identical to that of the MIP, with the exception that no template molecule is added. (Scheme.1)\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results and discussion","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e3.1 The structure and morphology characterization\u003c/h2\u003e \u003cp\u003eThe X-ray diffraction (XRD) patterns of SiO\u003csub\u003e2\u003c/sub\u003e, Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen complexes, and samples subjected to calcination at elevated temperatures were meticulously examined. (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e1\u003c/span\u003e) The result reveals that the XRD pattern of pure SiO\u003csub\u003e2\u003c/sub\u003e exhibits an amorphous structure, displaying amorphous peaks at approximately 2θ\u0026thinsp;=\u0026thinsp;24\u0026deg;, indicating an amorphous SiO\u003csub\u003e2\u003c/sub\u003e morphology. In Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e1\u003c/span\u003eb, the XRD pattern of Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen showcases a lack of prominent sharp peaks, but rather exhibits weak intensity and broader amorphous peaks at 2θ\u0026thinsp;=\u0026thinsp;10\u0026deg;, 20\u0026deg;, and 27\u0026deg;. These observations correspond to the characteristic crystalline peaks of the Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen rare-earth complex, thereby affirming the successful synthesis of the Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen rare-earth complex. Upon the addition of SiO\u003csub\u003e2\u003c/sub\u003e and subsequent calcination at 200 ℃, Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e1\u003c/span\u003ea exhibits the emergence of characteristic peaks corresponding to the Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen rare-earth complexes at 2θ\u0026thinsp;=\u0026thinsp;8\u0026deg; and 8.7\u0026deg;. This signifies that the incorporation of SiO\u003csub\u003e2\u003c/sub\u003e and the resulting calcined composites possess enhanced stability and crystallinity in comparison to the pristine Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen rare-earth complexes. Furthermore, it is noteworthy that the SiO\u003csub\u003e2\u003c/sub\u003e amorphous peak remains detectable at 2θ\u0026thinsp;=\u0026thinsp;24\u0026deg;, affirming the successful binding between the rare-earth complexes and SiO\u003csub\u003e2\u003c/sub\u003e.\u003c/p\u003e \u003cp\u003eThe infrared spectra of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen,SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP and SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SNIP were analyzed to gain insights into their respective profiles. As given in Figure.2 (a), it can be clearly seen that the characteristic Si-OH absorption peak at 3428 cm\u003csup\u003e-1\u003c/sup\u003e, indicating the presence of SiO\u003csub\u003e2\u003c/sub\u003e.The absorbed peaks at 1095 cm\u003csup\u003e-1\u003c/sup\u003e and 789 cm\u003csup\u003e-1\u003c/sup\u003e correspond to asymmetric and symmetric stretching vibrations of Si-O-Si, respectively, further confirming the successful formation of SiO\u003csub\u003e2\u003c/sub\u003e. Additionally, a peak at 464 cm\u003csup\u003e-1\u003c/sup\u003e corresponds to the symmetric telescopic vibrational peaks of Si-O-Si, further supporting the presence of SiO\u003csub\u003e2\u003c/sub\u003e. The characteristic absorption peak of Phen in rare earth complexes, represented by the C\u0026thinsp;=\u0026thinsp;N peak at 1381 cm\u003csup\u003e-1\u003c/sup\u003e, provides evidence of the successful preparation and effective combination of rare-earth complexes with SiO\u003csub\u003e2\u003c/sub\u003e. Furthermore, a slight fluctuation peak at 2918 cm\u003csup\u003e-1\u003c/sup\u003e indicates that CTAB, a surfactant, has been almost eliminated through calcination. The successful modification of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen by KH-570 is also evidenced by the appearance of a characteristic C\u0026thinsp;=\u0026thinsp;C stretching vibration peak at 1631 cm\u003csup\u003e-1\u003c/sup\u003e.The increase in the peak at 1384 cm\u003csup\u003e-1\u003c/sup\u003e suggests the presence of a C-H bending vibration peak in MAA (methacrylic acid). The original C\u0026thinsp;=\u0026thinsp;C characteristic peak at 1631 cm\u003csup\u003e-1\u003c/sup\u003e undergoes a shift to 1628 cm\u003csup\u003e-1\u003c/sup\u003e, accompanied by a significant increase in intensity. This shift indicates that after the initial C\u0026thinsp;=\u0026thinsp;C modification, the C\u0026thinsp;=\u0026thinsp;C in MAA masks the original peak, resulting in its intensified appearance. Another peak emerges at 1589.1 cm\u003csup\u003e-1\u003c/sup\u003e, corresponding to the -COOH- characteristic absorption peak in the MAA structure. This peak signifies the binding of MAA to the surface of the microsphere. The simultaneous increase in these two peaks suggests the successful polymerization of the imprinted layer. (Figure.2b and Figure.2c)\u003c/p\u003e \u003cp\u003eIn order to study the element composition of the sample, the as-prepared SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP were analyzed by X-ray photoelectron spectroscopy (XPS) and the results are shown in Figure.S1. Figure.S1 (a) presents the comprehensive XPS spectrum of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP, revealing the presence of five elements, namely O, C, Si, N, and Eu. Figure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e(b) focuses on a narrow scan of C1s, wherein the peaks at 288.4 eV, 286.2 eV, and 284.4 eV correspond to C\u0026thinsp;=\u0026thinsp;O, C-O, and C\u0026thinsp;=\u0026thinsp;C/C-C functional groups, respectively. This observation confirms the successful modification of KH-570 and the polymerization of MAA. In Figure S2(a), it showcases four peaks at 1164 eV, 1154 eV, 1134.7 eV, and 1125 eV, which correspond to Eu3d\u003csup\u003e3/2\u003c/sup\u003e, Eu3d\u003csup\u003e3\u003c/sup\u003e, Eu3d\u003csup\u003e5/2\u003c/sup\u003e, and Eu3d\u003csup\u003e5\u003c/sup\u003e, respectively. These peaks are attributed to the effects of rare-earth compatibilities on the SiO\u003csub\u003e2\u003c/sub\u003e combination, leading to alterations in the structure of excited state energy levels. This, in turn, corresponds to adjustments in excitation wavelengths and changes in electronic leaps during fluorescence detection. Figure S2(b) focuses on the narrow scan of N1s, revealing two peaks at 399.2 eV and 402.48 eV, which can be assigned to C-N-C and N-H, respectively. The primary source of nitrogen (N) is the ENFX template, and the lower peak suggests the effective elution of ENFX from the probe. The appearance of the N-H peak is mainly attributed to the formation of hydrogen bonding between the functional monomers and the template. Figure S3(a) exhibits a secondary occurrence of C\u0026thinsp;=\u0026thinsp;O at 532.3 eV and 532.6 eV, corresponding to C\u0026thinsp;=\u0026thinsp;O and C-OH/O-C-O, respectively. This result implies that the C\u0026thinsp;=\u0026thinsp;O contributions originate from two different substances, indicating the successful grafting of both the KH-570 modification and free radical polymerization onto the surface of the fluorescent microspheres. Finally, Figure S3(b) focuses on a narrow scan of Si2p, which reveals the presence of two peaks at 102.98 eV and 101.78 eV corresponding to Si-O and Si-C, respectively. These findings all confirm the existence of SiO\u003csub\u003e2\u003c/sub\u003e and provide further support for the success of the KH-570 modification, aligning with the C\u0026thinsp;=\u0026thinsp;C plot observed in the FT-IR spectrum., respectively, confirming the presence of SiO\u003csub\u003e2\u003c/sub\u003e as well as corroborating the success of the KH-570 modification, which corresponds to the C\u0026thinsp;=\u0026thinsp;C plot in the FT-IR spectrum.\u003c/p\u003e \u003cp\u003e \u003cb\u003e3.2 Fluorescence properties\u003c/b\u003e The morphology of the as-obtained samples was investigated by SEM.(Figure.3) Notably, the calcinated SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen microspheres(b) exhibit an average particle size of approximately 200 nm, boasting a smooth surface. However, it is worth mentioning that some of the fluorescent microspheres showcase partial aggregation, a phenomenon which can be ascribed to the relatively low incorporation of CTAB as a soft template, resulting in a certain degree of agglomeration. In comparison to the morphology of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen fluorescent microspheres depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e3\u003c/span\u003e(a), the surface of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP unveils a uniform molecularly imprinted layer of enrofloxacin. Because of the crosslinker initiating the free radical polymerization reaction, the agglomeration phenomenon induced by the addition of CTAB becomes more pronounced.\u003c/p\u003e \u003cp\u003eA specified quantity of the product SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP was dissolved in ethanol. After subjecting it to ultrasonic dispersion, 3 mL of the well-dispersed solution was taken and combined with varying concentrations of enrofloxacin. The mixture was then incubated for a duration of 10 minutes at room temperature, during which the fluorescence intensity of each solution was recorded. The fluorescence measurements were conducted under specific conditions: excitation at a wavelength of 278 nm, a slit width of 5 nm, and a scanning speed of 2000 nm/min.\u003c/p\u003e \u003cp\u003eUpon the examination of pure complex Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen, the emission spectrum exhibits a series of \u003csup\u003e5\u003c/sup\u003eD\u003csub\u003e0\u003c/sub\u003e\u0026rarr;\u003csup\u003e7\u003c/sup\u003eF\u003csub\u003e2\u003c/sub\u003e (J\u0026thinsp;=\u0026thinsp;0,1,2,3,4) (579,591,614,651,699 nm) transitions of Eu\u003csup\u003e3+\u003c/sup\u003e. Notably, the most intense emission peak corresponds to the aforementioned \u003csup\u003e5\u003c/sup\u003eD\u003csub\u003e0\u003c/sub\u003e\u0026rarr;\u003csup\u003e7\u003c/sup\u003eF\u003csub\u003e2\u003c/sub\u003e leaps, aligning with the documented electronic transitions of Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen in the literature\u003csup\u003e[\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]\u003c/sup\u003e. This compelling evidence confirms the successful preparation of the rare-earth complex Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen.Furthermore, Fig S4 reveals a distinct blue shift in the excitation wavelength, shifting from the pure rare earth coordination excitation wavelength of 306 nm to 280 nm for SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP. This phenomenon can primarily be attributed to the incorporation of the silica matrix, which induces modifications in the surrounding environment of the rare earths, consequently influencing the electronic transitions7. Moreover, the interactions between \u003csup\u003e5\u003c/sup\u003eD\u003csub\u003e0\u003c/sub\u003e\u0026rarr;\u003csup\u003e7\u003c/sup\u003eF\u003csub\u003e1\u003c/sub\u003e and \u003csup\u003e5\u003c/sup\u003eD\u003csub\u003e0\u003c/sub\u003e\u0026rarr;\u003csup\u003e7\u003c/sup\u003eF\u003csub\u003e3\u003c/sub\u003e transitions, as well as the observed enhancement of \u003csup\u003e5\u003c/sup\u003eD\u003csub\u003e0\u003c/sub\u003e\u0026rarr;\u003csup\u003e7\u003c/sup\u003eF\u003csub\u003e4\u003c/sub\u003e peaks and the reduction of \u003csup\u003e5\u003c/sup\u003eD\u003csub\u003e0\u003c/sub\u003e\u0026rarr;\u003csup\u003e7\u003c/sup\u003eF\u003csub\u003e0\u003c/sub\u003e transitions, can be attributed to the energetic interaction between these transitions, ultimately leading to an increase in the excited state electronic energy level of the system. These findings robustly support the notion of a favorable binding morphology between SiO\u003csub\u003e2\u003c/sub\u003e and the rare earth complexes.\u003c/p\u003e \u003cp\u003eTo optimize the assay for burst rate, two parameters, namely probe concentration and incubation time, were meticulously evaluated. It is important to note that excessively high probe concentration or insufficient incubation time could lead to a low quenching rate, rendering the detection experiments unsuitable for the substance under investigation. Hence, in this study, we explored the optimal detection system probe concentration by varying the concentration of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP from 0.1 mg/mL to 0.6 mg/mL and measuring its effect on the detection of ENFX at a concentration of 100 \u0026micro;M. Figure S5(b) illustrates that a low probe concentration leads to a significant fluorescence burst upon addition of ENFX, which gradually decreases as the concentration of the former increases beyond 0.3 mg/ml. Therefore, taking into consideration both the fluorescence intensity and burst rate, a fluorescent probe concentration of 0.35 mg/ml was deemed optimal. Furthermore, the incubation time was identified as another crucial factor influencing the fluorescent probe. Figure S5(a) provides evidence that the fluorescence burst rate tends to stabilize after an incubation time of 8 minutes. Hence, for subsequent fluorescence performance testing experiments, the incubation time was fixed at 8 minutes, and the concentration of the probe was maintained at 0.35 mg/ml.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Sensing detection performance of the fluorescent probe\u003c/h2\u003e \u003cp\u003eTo investigate the specific recognition and detection capabilities of the SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP probe towards ENFX, four fluoroquinolone antibiotics, namely Lomefloxacin Hydrochlorde (LOM), Sparfloxasin (SPFX), Levofloxacin (OFLX), and Ciprofloxacin (CIP), were selected for comparation, all the structures were illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e4\u003c/span\u003e(b). Furthermore, the structures of MIP and NIP were utilized for the burst (F\u003csub\u003e0\u003c/sub\u003e/F) experiments with the concentration of 200 \u0026micro;M. From Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e4\u003c/span\u003e(a), it is evident that both MIP and NIP exhibit a certain degree of bursting upon exposure to fluoroquinolone antibiotics, with comparable levels of intensity. However, the bursting effect of MIP on ENFX was notably stronger when compared to the other antibiotics of identical structure. This enhanced effect can be attributed to the presence of specific binding sites for ENFX within the molecular imprinting layer, leading to the selective recognition of ENFX by SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP. These findings affirm that the superior specific recognition and detection performance of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen /SMIP for ENFX.\u003c/p\u003e \u003cp\u003eTo assess the sensitivity of the fluorescence response of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003e Phen/SMIP, a series of ENFX standard solutions with varying concentrations (20\u0026thinsp;~\u0026thinsp;100 \u0026micro;M) were prepared and added to the SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP solution. The fluorescence intensity values were measured before and after mixing, following 8 minutes interaction between the two. As depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e5\u003c/span\u003e(a), the intensity of the molecularly imprinted fluorescent probe exhibited a significant decrease in the range of 100\u0026thinsp;~\u0026thinsp;70 \u0026micro;M with the gradual increase of ENFX concentration. The fluorescence burst effect tended to level off as the concentration of the detector was reduced to 30 \u0026micro;M. A good linear relationship between the fluorescence burst rate (F\u003csub\u003e0\u003c/sub\u003e/F) of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP and the concentration of ENFX in the range of 20\u0026thinsp;~\u0026thinsp;100 \u0026micro;M was observed, as illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e5\u003c/span\u003e(b). The fluorescence quenching constant of Stern-Volmer, K\u003csub\u003esv\u003c/sub\u003e, was determined using the equation \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\text{F}\\text{0}\u0026frasl;\\text{F}=\\text{K}\\text{sv}\\left[\\text{C}\\right]+1\\)\u003c/span\u003e\u003c/span\u003e, where F\u003csub\u003e0\u003c/sub\u003e is the fluorescence intensity of the molecularly imprinted probe before the addition of ENFX, and F is the fluorescence intensity after the addition of different concentrations of ENFX. C represents the concentration of added ENFX. This was fitted to obtain the linear regression equation:\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\text{F}\\text{0}/\\text{F}=0.00271\\text{C}\\text{e}\\text{n}\\text{r}+1.11764\\)\u003c/span\u003e\u003c/span\u003e, with an R\u003csup\u003e2\u003c/sup\u003e value of 0.99225, and a fluorescence quenching constant of 0.00271. Based on the standard deviation of the blank signal obtained from five consecutive detections, δ, and the slope of the linear equation, S, the limit of detection (LOD) was calculated as LOD=3.07 \u0026micro;M. The LOD could be further improved to 1.5 \u0026micro;M within the range of 20~100 \u0026micro;M, based on the linear relationship between the fluorescence quenching rate and the concentration of added ENFX for SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP. In addition, the blotting effect was examined by investigating the fluorescence detection performance of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SNIP under the same assay conditions. The linear regression equation \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\text{F}\\text{0}\\text{/F=0.00224Cenr+0.00157}\\)\u003c/span\u003e\u003c/span\u003e, with an R\u003csup\u003e2\u003c/sup\u003e value of 0.9758, and a fluorescence burst constant of K\u003csub\u003esv\u003c/sub\u003e(NIP)=0.00224 were derived using the Stern-Volmer equation. The imprinting factor, IF, was calculated according to the formula IF=K\u003csub\u003esv\u003c/sub\u003e(MIP)/K\u003csub\u003esv\u003c/sub\u003e(NIP), yielding a value of 1.2098. These results demonstrate the superior sensitivity and specificity of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP as a molecular fluorescence probe for the detection of ENFX.\u003c/p\u003e \u003cp\u003eMoreover, we have undertaken experiments to assess the impact of individual metal ions and acid radical ions on the efficacy of molecularly imprinted probes in mitigating interference. The selectivity of the SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP sensor for ENFX was explored by selecting the different ions including Cu\u003csup\u003e2+\u003c/sup\u003e, Na\u003csup\u003e+\u003c/sup\u003e, Mn\u003csup\u003e2+\u003c/sup\u003e, Ni\u003csup\u003e2+\u003c/sup\u003e, K\u003csup\u003e+\u003c/sup\u003e, Co\u003csup\u003e2+\u003c/sup\u003e, Cl\u003csup\u003e-\u003c/sup\u003e, and SO\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e2-\u003c/sup\u003e.(Fig. S8) As a result, all these ions did not exert any discernible effect on the fluorescence emission of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP. This suggests that the detection of ENFX by SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP may remain unaffected by fluoroquinolone homologs antibiotics and diverse metal ions. These results unequivocally demonstrate that SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP exhibits exceptional specific recognition ability, detection performance, and resilience against interference in the detection of ENFX.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e3.4 Adsorption properties of the probe SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP\u003c/h2\u003e \u003cp\u003eTo investigate the adsorption rate of the SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP fluorescent probe on the target ENFX and ascertain the presence of specific binding sites, the adsorption capacities of MIP and NIP on ENFX were measured at various times, as depicted in Fig S6. The adsorption equilibrium time for SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP was found to be 30 minutes, with an adsorption capacity of 1.75 mg/g. In contrast, the adsorption equilibrium time for SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SNIP was 20 minutes, with an adsorption capacity of 1.61 mg/g. This difference in adsorption capacity is attributed to the existence of specific binding sites within SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP, resulting in a greater adsorption capacity for ENFX. This finding further confirms the presence of a molecularly imprinted layer with specific recognition capabilities. To further explore the adsorption capacity of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP on the target ENFX, varied concentrations of ENFX solutions were prepared for static adsorption experiments. As illustrated in Figure S7, the adsorption capacity of MIP and NIP exhibited a progressive increase with the ascending concentration of ENFX. Additionally, the adsorption capacity of MIP surpassed that of NIP, with the maximum adsorption capacity of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP (54.64 mg/g) being 1.08 times that of NIP when the concentration reached 500 mg/L. These findings suggest that the probe possesses admirable adsorption characteristics, while the presence of specific sites after the blotting elution template elevates the adsorption capacity of ENFX.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e3.5 Application to the actual sample detection\u003c/h2\u003e \u003cp\u003eTo evaluate the applicability and reliability of the proposed SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP fluorescence system, real sample testing was conducted using milk and the drinking water to investigate the performance of the SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP in practical ENFX, detection (See Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e). The standard addition (recovery) method was employed to detect ENFX in the real sampls. Specifically, we have expanded the range of detection for low concentrations in actual samples, selecting 5 \u0026micro;M and 10 \u0026micro;M as the test concentrations, and obtained the results of the recovery rate through calculations involving the added standards. In the detection of actual samples, the scalar added is typically 0.5 to 2.0 times the content of the analyte. The concentration of the added standard should be high, and the volume should be controlled within a small range, usually not exceeding 1% of the volume of the original sample. If the recovery rate exceeds 100%, it may indicate that the added amount is too large or that there is an error in the measured value. The ideal range for the recovery rate is generally between 90% and 110%, with values closer to 100% indicating higher reliability of the data. According to the calculation results presented in Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e, the recovery rates are close to 100% within the detection range and approach 100% at low concentrations near the limit of detection. These findings confirm the applicability of this fluorescence probe for the analysis of real samples.\u003c/p\u003e \u003c/div\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eIn summary, we have successfully developed the molecularly imprinted particle generated through surface-imprinted polymerization exhibited remarkable levels of recognition specificity towards enrofloxacin. The fluorescent microspheres demonstrated strong fluorescence emission, attributed mainly to the transfer of energy from the two ligands, DBM and Phen, to the Eu\u003csup\u003e3+\u003c/sup\u003e ions via the antenna effect. SiO\u003csub\u003e2\u003c/sub\u003e is suitable as substrate for surface imprinting materials, and the combination with Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen can further enhance the mechanical strength, thermal stability and fluorescence stability of fluorescent microspheres. The blotting microspheres manifested a sensitive and rapid fluorescence response to ENFX, with a low detection limit and excellent specificity. These results suggest a broad potential for the application of this technology in surface blotting and aquatic product detection.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eSupplementary Information\u0026nbsp;\u003c/strong\u003eLanthanide complexes and fluorescent microsphere emission profiles for electron jumps. XPS spectra of SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ePhen/SMIP and high-resolution spectra of C1s,N1s,O1s,Si2p,Eu3d.Optimization of molecular blotting concentration and incubation time experiments. Dynamic adsorption profiles of MIP/NIP to enrofloxacin.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e Huang Xiaoqing and Wang Maoyu: experiments, data analysis, investigation, writing - initial draft, Li Ying\u0026apos;s writing - comments and editing. Wang Xiaochen investigates and writes - initial draft. Shi Xin, Li Ruisi, and Wu Shuang: Data organization, analysis, and investigation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFounding\u0026nbsp;\u003c/strong\u003eThis work was supported by the National Natural Science Foundation of China (21101107, 51173107), State Key Laboratory of Pollution Control and Resource Reuse Foundation, (NO. PCRRF19017)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo datasets were generated or analysed during the current study\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical approval\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable (this research does not involve human or animal samples).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u0026nbsp;\u003c/strong\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eM. Rusch, A. Spielmeyer, H. Zorn, G. Hamscher, Degradation and transformation of fluoroquinolones by microorganisms with special emphasis on ciprofloxacin, Appl Microbiol Biotechnol, 103 (2019) 6933-6948,https://10.1007/s00253-019-10017-8\u003c/li\u003e\n\u003cli\u003eG. Drusano, M.-T. Labro, O. Cars, P. Mendes, P. Shah, F. S\u0026ouml;rgel, W. 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Sun, Synthesis of silica/rare-earth complex hybrid luminescence materials with cationic surfactant and their photophysical properties, Journal of Physics and Chemistry of Solids, 133 (2019) 79-84,https://10.1016/j.jpcs.2019.05.011\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Scheme","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":"Lanthanide complexes, surface imprinting, Enrofloxacin detection, SiO2","lastPublishedDoi":"10.21203/rs.3.rs-6545537/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6545537/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eEnrofloxacin (ENFX), being an antibiotic of notable distinction, serves as a specialized therapeutic agent for the mitigation of animal afflictions. However, the potential ingestion of enrofloxacin through the consumption of animal-derived sustenance can give rise to a multitude of concerns such as toxicity, drug resistance, and allergic reactions. Therefore, it becomes imperative to embrace measures that expedite the quantification of enrofloxacin levels, ensuring timely detection and assessment. Herein, a surface-imprinted polymer SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ephen/SMIP was synthesized using ENFX as a template molecule, methacrylic acid as a functional monomer, and Tris(dibenzoyl methane)(1,10-phenanthroline)europium(III) as a fluorescent moiety. SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ephen/SMIP performs high selectivity and the low detection limit toward enrofloxacin. The specificity assay revealed its remarkable selectivity for four other fluoroquinolone antibiotics, while the rare-earth complexes displayed exceptional chemical stability, showing no significant interference from metal ions or reactive oxygen species. The results indicate that it is feasible to use SiO\u003csub\u003e2\u003c/sub\u003e@Eu(DBM)\u003csub\u003e3\u003c/sub\u003ephen/SMIP for the detection of ENFX as well as effective adsorption. This study investigates the self-assembly of rare-earth complexes on silica using suggestive blotting technique, which provides a new solution for the subsequent development of surface blotting technique.\u003c/p\u003e","manuscriptTitle":"A surface-imprinting lanthanide fluorescent hybrid probe on the SiO2 microspheres for the detection of the enrofloxacin","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-07 12:17:29","doi":"10.21203/rs.3.rs-6545537/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-05-17T07:09:27+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-12T04:48:18+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-08T17:39:24+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-03T15:18:25+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"39889191300099536352269261262921143883","date":"2025-05-03T07:19:08+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"120251281515822197903652997859382082278","date":"2025-05-02T10:12:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"230161838623075700930244046154090178337","date":"2025-05-02T07:37:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"111381097341840495820841814658774504596","date":"2025-05-02T07:36:21+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-05-02T07:26:28+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-04-30T20:51:30+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-04-30T09:30:55+00:00","index":"","fulltext":""},{"type":"submitted","content":"Microchimica Acta","date":"2025-04-28T08:14:54+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":"73a154d6-ade2-4097-9148-b05d01b919c1","owner":[],"postedDate":"May 7th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-08-04T16:41:50+00:00","versionOfRecord":{"articleIdentity":"rs-6545537","link":"https://doi.org/10.1007/s00604-025-07369-6","journal":{"identity":"microchimica-acta","isVorOnly":false,"title":"Microchimica Acta"},"publishedOn":"2025-07-29 16:21:12","publishedOnDateReadable":"July 29th, 2025"},"versionCreatedAt":"2025-05-07 12:17:29","video":"","vorDoi":"10.1007/s00604-025-07369-6","vorDoiUrl":"https://doi.org/10.1007/s00604-025-07369-6","workflowStages":[]},"version":"v1","identity":"rs-6545537","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6545537","identity":"rs-6545537","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}