A kanamycin-responsive perovskite-based ratio fluorescent biomimetic sensing material, a preparation method and application thereof
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HEBEI AGRICULTURAL UNIV.
- Filing Date
- 2026-04-15
- Publication Date
- 2026-06-23
AI Technical Summary
Existing kanamycin detection methods require complex and expensive instruments or complicated sample pretreatment, which limits their practical application and prevents them from achieving simple and sensitive detection.
A kanamycin-responsive perovskite-based ratiofluorescent biomimetic sensing material was prepared by combining molecular imprinting technology with perovskite quantum dots. The material utilizes green fluorescent perovskite quantum dots as the response signal and red europium metal-organic frameworks as the reference signal. By combining the post-imprinting modification strategy of molecular imprinting technology, sensitive detection of kanamycin can be achieved.
It achieves sensitive and selective detection of kanamycin, is simple to operate, and is suitable for the detection of kanamycin in food. It has good stability and anti-interference ability, and achieves visual detection through ratio fluorescence response.
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Abstract
Description
Technical Field
[0001] This invention relates to the technical fields of polymer optical sensing material preparation methods and antibiotic detection methods, and in particular to a kanamycin-responsive perovskite-based ratio fluorescence biomimetic sensing material, its preparation method, and its application. Background Technology
[0002] Kanamycin (KANA) is an aminoglycoside antibiotic widely used to treat bacterial infections in aquaculture and livestock due to its strong antibacterial properties. However, residual kanamycin poses certain safety risks: long-term or excessive use of kanamycin can result in large amounts of antibiotic residues in food. Consuming food with excessive kanamycin residues can lead to serious liver toxicity, kidney toxicity, and ototoxicity. Furthermore, residues may increase bacterial resistance to antibiotics, and worse, pollute water and soil environments. Due to its potential toxicity to human health, many countries have restricted the use of kanamycin and have imposed strict limits on kanamycin residues in animal-derived foods. For example, China has specified minimum residue limits for kanamycin in a range of foods, including liver (600 ppb), muscle tissue (100 ppb), kidney (2500 ppb), and dairy products (150 ppb). To achieve monitoring, various methods have been developed both domestically and internationally for the detection of KANA, particularly traditional methods such as high-performance liquid chromatography (HPLC), chemiluminescence immunoassay, capillary electrophoresis (CE), and colorimetric strip methods. However, these methods typically require complex and expensive instruments or complex sample pretreatment, which limits their practical application. Therefore, it is essential to develop KANA detection materials and methods that are simple to operate and highly sensitive, without relying on complex and expensive instruments. Summary of the Invention
[0003] The purpose of this invention is to provide a kanamycin-responsive perovskite-based ratio fluorescence biomimetic sensing material, its preparation method, and its application, in order to solve the problems existing in the prior art.
[0004] To achieve the above objectives, the present invention provides the following solution: One of the technical solutions of the present invention: a method for preparing a kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material, comprising the following steps: Europium metal-organic framework materials (TB-Eu-MOFs), kanamycin, and buffer solution were mixed, stirred, and centrifuged. The precipitate was dispersed in solvent 1, methacrylic acid was added, and the mixture was stirred. Then, ethylene glycol dimethacrylate and an initiator were added to carry out a thermal polymerization reaction. The mixture was then centrifuged, washed, and dried to obtain europium metal-organic framework molecularly imprinted polymers (TB-Eu-MOFs@MIPs). The europium metal-organic framework molecularly imprinted polymer was mixed with lead bromide, cesium bromide, 4-bromobutyric acid, oleylamine, N,N-dimethylacetamide, and N,N-dimethylpropionamide, and the mixture was heated and stirred to obtain a perovskite quantum dot precursor solution. The perovskite quantum dot precursor solution was mixed with a rubidium bromide solution and heated and stirred to obtain a perovskite quantum dot-europium metal-organic framework molecularly imprinted polymer composite material (abbreviated as TB-Eu-MOFs@MIPs@CsPbBr3-Rb), which is the kanamycin-responsive perovskite-based ratio fluorescence biomimetic sensing material.
[0005] Molecular imprinting (MIT) is a biomimetic molecular recognition technology that mimics the specific recognition interactions of antigen-antibody and enzyme-substrate interactions. MIT-based molecularly imprinted polymers (MIPs) possess numerous advantages, including good physical and chemical stability, strong affinity, good selectivity and adsorption, simple preparation, and low cost. Perovskite quantum dots, on the other hand, exhibit excellent optical properties (high quantum yield, narrow emission, and tunable wavelength) and ease of modification, while quantum dot fluorescence detection technology offers high sensitivity. This invention combines molecular imprinting with perovskite quantum dots to prepare a kanamycin-responsive perovskite-based ratiometric fluorescence biomimetic sensing material. The ratiometric fluorescence biomimetic sensing material prepared using the method of this invention uses green fluorescent perovskite quantum dots as the response signal and red europium metal-organic frameworks as the reference signal. Combined with the post-imprinting modification strategy of molecular imprinting, it can achieve sensitive detection of kanamycin. Using this material for kanamycin detection is not only sensitive and selective but also simple to operate, showing promising application prospects for the detection of kanamycin in food.
[0006] Furthermore, the buffer solution includes a Tris-HCl buffer solution.
[0007] Furthermore, the concentration of the Tris-HCl buffer solution is 45-55 mM, and the pH value is 8-9.
[0008] Furthermore, solvent 1 includes ethanol.
[0009] Furthermore, the initiator includes azobisisobutyronitrile.
[0010] Further, the ratio of the europium metal-organic framework material, the kanamycin, the methacrylic acid, the ethylene glycol dimethacrylate, and the initiator is 40-80 mg:0.2 mmol:0.6-1.8 mmol:1-2.2 mmol:40 mg.
[0011] Furthermore, the ratio of the europium metal-organic framework material to the buffer solution is 40-80 mg:20 mL.
[0012] Furthermore, the mass ratio of the europium metal-organic framework material corresponding to the centrifuged precipitate to the volume of solvent 1 is 40-80 mg: 20 mL.
[0013] Furthermore, the europium metal-organic framework material, kanamycin, and buffer solution were mixed and stirred at a temperature of 20-30 °C (i.e., room temperature) for 1-3 h.
[0014] Furthermore, after adding methacrylic acid, the reaction temperature is 20-30 ℃ (i.e., room temperature), and the reaction time is 2-4 h.
[0015] Furthermore, the addition of ethylene glycol dimethacrylate and the initiator includes an ultrasonic treatment step.
[0016] Furthermore, the temperature of the thermal polymerization reaction is 60-70 °C, and the time is 2-3 h.
[0017] Furthermore, the process includes a step of purging with nitrogen to remove oxygen and then sealing the container before the thermal polymerization reaction.
[0018] Furthermore, the nitrogen deoxygenation time is 10-30 minutes.
[0019] Furthermore, the washing process specifically involves washing three times with ethanol and then washing 10-13 times with 0.1 mol acetic acid solution; the drying process specifically involves drying at 40 ℃ for 10-14 h.
[0020] Furthermore, the ratio of the europium metal-organic framework molecularly imprinted polymer, the lead bromide, the cesium bromide, the 4-bromobutyric acid, the oleylamine, the N,N-dimethylacetamide, and the N,N-dimethylpropionamide is 125-200 mg: 0.2 mmol: 0.2 mmol: 1 mmol: 1 mmol: 3 mL: 2 mL.
[0021] Furthermore, the europium metal-organic framework molecularly imprinted polymer is mixed with lead bromide, cesium bromide, 4-bromobutyric acid, oleylamine, N,N-dimethylacetamide and N,N-dimethylpropionamide, and then heated and stirred at a temperature of 65-75 °C for 8-12 h.
[0022] Furthermore, the volume ratio of the perovskite quantum dot precursor solution to the molar amount of rubidium bromide in the rubidium bromide solution is 2-3 mL:2 mmol.
[0023] Furthermore, the rubidium bromide solution is prepared from rubidium bromide and water.
[0024] Furthermore, the ratio of rubidium bromide to water is 2 mmol: 30-35 mL.
[0025] Furthermore, the perovskite quantum dot precursor solution is mixed with the rubidium bromide solution and then heated and stirred at a temperature of 65-75 °C for 20-40 min.
[0026] Furthermore, the preparation steps of the europium metal-organic framework material include: mixing europium source, terephthalic acid, 2,5-dicarboxyphenylboronic acid and solvent 2, stirring and reacting, and then heating to obtain the europium metal-organic framework material.
[0027] Furthermore, the europium source includes EuCl3·6H2O.
[0028] Furthermore, the molar ratio of the europium source, the terephthalic acid, and the 2,5-dicarboxyphenylboronic acid is 0.2:0.18:0.02.
[0029] Furthermore, solvent 2 is a mixed solvent of N,N-dimethylformamide and water.
[0030] Furthermore, the volume ratio of N,N-dimethylformamide to water in solvent 2 is 7:3. Furthermore, the ratio of europium source to solvent 2 is 0.1 mmol: 8-12 mL.
[0031] Furthermore, the temperature of the stirring reaction is 20-30 °C, and the time is 1-3 h.
[0032] Furthermore, the heating reaction is carried out at a temperature of 120-140 °C for a duration of 10-14 h.
[0033] Furthermore, the heating reaction is preceded by a step of purging with nitrogen to remove oxygen.
[0034] Furthermore, after the heating reaction is completed, the process includes centrifugation, washing, and drying. Specifically, the washing involves washing three times with a mixed solution of N,N-dimethylformamide and anhydrous ethanol, followed by washing 1-2 times with anhydrous ethanol.
[0035] The second technical solution of the present invention: a kanamycin-responsive perovskite-based ratio fluorescence biomimetic sensing material prepared by the above-described method.
[0036] The third technical solution of the present invention: the application of the above-mentioned kanamycin-responsive perovskite-based ratio fluorescence biomimetic sensing material in kanamycin detection.
[0037] Furthermore, the application specifically refers to its use in the detection of kanamycin in food.
[0038] The present invention discloses the following technical effects: This invention proposes a reliable dual-mode kanamycin-responsive perovskite-based ratiometric fluorescence biomimetic sensing material, TB-Eu-MOFs@MIPs@CsPbBr3-Rb (dual-mode means TB-Eu-MOFs@MIPs@CsPbBr3-Rb possesses both "quantitative fluorescence detection" and "visual color response" functions: the former relies on fluorescence intensity-concentration standards for accurate analysis, while the latter achieves rapid screening through discernible color changes). This sensing material utilizes its ratiometric fluorescence properties to achieve precise quantification of kanamycin and integrates dual recognition units to enhance selectivity and anti-interference capabilities. In this invention, TB-Eu-MOFs, as a structurally regular substrate and stable reference signal, not only provide an ideal platform for modifying the surface imprint layer to introduce recognition sites, but also reduce mass transfer resistance due to its high specific surface area and porosity, thereby amplifying the sensing signal. TB-Eu-MOFs@MIPs, prepared using a boric acid affinity-oriented surface molecular imprinting (BA-COSMI) strategy, possess both covalent boric acid affinity sites and non-covalently imprinted holes, endowing the sensing material with excellent selective recognition and preferential binding capabilities. They exhibit bright green fluorescence. (λ) em = 520 nm ） CsPbBr3-Rb was introduced as a response signal via post-imprinting modification. In the presence of the target analyte kanamycin, it underwent significant fluorescence quenching through a synergistic effect of dynamic quenching and photoinduced electron transfer (PET). In contrast, TB-Eu-MOFs exhibited red fluorescence. (λ) em = 620 nm ） The stability demonstrated by the high sensitivity of the ratio fluorescence response, accompanied by a distinct color transition from green to yellow-green, light pink, and finally magenta, allows for controllable adjustment of the ratio fluorescence signal and enables its use in the visual detection of kanamycin.
[0039] The kanamycin-responsive perovskite-based ratio fluorescence biomimetic sensing material of the present invention is prepared by chemical synthesis, which is low in cost and simple to operate, and is suitable for the detection of kanamycin in food. During the detection process, the material exhibits good stability, excellent selectivity and strong anti-interference ability. Attached Figure Description
[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0041] Figure 1 The diagram shows the preparation route of kanamycin-responsive perovskite-based ratio fluorescent biomimetic sensing material and the principle of its detection. (A) is the preparation route of TB-Eu-MOFs, (B) is the preparation route of TB-Eu-MOFs@MIPs, and (C) is the preparation route of TB-Eu-MOFs@MIPs@CsPbBr3-Rb and the principle of its detection.
[0042] Figure 2 Fourier transform infrared spectra of TB-Eu-MOFs, TB-Eu-MOFs@MIPs, TB-Eu-MOFs@NIPs, TB-Eu-MOFs@MIPs@CsPbBr3-Rb, and TB-Eu-MOFs@NIPs@CsPbBr3-Rb.
[0043] Figure 3 Scanning electron microscope (SEM) images of TB-Eu-MOFs (A), TB-Eu-MOFs@MIPs (B), and TB-Eu-MOFs@MIPs@CsPbBr3-Rb (C); transmission electron microscope (TEM) images of TB-Eu-MOFs (D), TB-Eu-MOFs@MIPs (E), and TB-Eu-MOFs@MIPs@CsPbBr3-Rb (F); TEM image (G) and high-resolution TEM image (H) of CsPbBr3-Rb; and high-resolution TEM image (I) of TB-Eu-MOFs@MIPs@CsPbBr3-Rb.
[0044] Figure 4 Scanning electron microscope (SEM) images of TB-Eu-MOFs@NIPs (A) and TB-Eu-MOFs@NIPs@CsPbBr3-Rb (B); transmission electron microscope (TEM) images of TB-Eu-MOFs@NIPs (C) and TB-Eu-MOFs@NIPs@CsPbBr3-Rb (D).
[0045] Figure 5 The response curves of TB-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Example 1 to different concentrations of KANA.
[0046] Figure 6 Adsorption kinetic curves of TB-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Example 1, TB-Eu-MOFs@NIPs@CsPbBr3-Rb prepared in Comparative Example 1, and MIPs@CsPbBr3-Rb prepared in Comparative Example 2.
[0047] Figure 7 The adsorption specificity test results of TB-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Example 1, TB-Eu-MOFs@NIPs@CsPbBr3-Rb prepared in Comparative Example 1, and T-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Comparative Example 3 are presented.
[0048] Figure 8 The color changes of TB-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Example 1 in three parallel experiments with different concentrations of KANA. Detailed Implementation
[0049] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.
[0050] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.
[0051] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.
[0052] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.
[0053] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.
[0054] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.
[0055] In the following embodiments, comparative examples and test examples of the present invention, if room temperature is involved, it specifically refers to 20-30°C.
[0056] Unless otherwise specified, all raw materials used in the following embodiments, comparative examples and test examples of this invention are commercially available products.
[0057] Example 1 A kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material, the preparation steps of which are illustrated in the schematic diagram below. Figure 1 As shown in (A)-(C), the following is an example: (1) Take 0.2 mmol of EuCl3·6H2O, 0.18 mmol of terephthalic acid, and 0.02 mmol of 2,5-dicarboxyphenylboronic acid, add them to a mixed solvent of 14 mL of N,N-dimethylformamide and 6 mL of water, stir at room temperature for 2 h, then purge with nitrogen for 15 min to remove oxygen, transfer to a high-pressure reactor, react at 130 ℃ for 12 h, sonicate for 15 min, centrifuge at 4000 rpm for 10 min, wash three times with a mixed solution of N,N-dimethylformamide and anhydrous ethanol (volume ratio of 14:6), wash twice with anhydrous ethanol, and then dry at 40 ℃ for 12 h to obtain europium metal-organic framework materials (denoted as TB-Eu-MOFs).
[0058] (2) Take 60 mg of europium metal-organic framework material (TB-Eu-MOFs) and 0.2 mmol of kanamycin and add them to 20 mL of Tris-HCl buffer solution (pH 8.5, 50 mM). Stir at room temperature for 2 h. After centrifugation, the precipitate is dispersed in 20 mL of ethanol. Add 1 mmol of methacrylic acid (MAA) and stir at room temperature for 3 h. Then add 1.4 mmol of ethylene glycol dimethacrylate (EGDMA) and 40 mg of azobisisobutyronitrile. Sonicate to dissolve and disperse evenly. After purging with nitrogen for 15 min, seal and carry out thermal polymerization reaction in a 65 ℃ water bath for 2 h. After the reaction is completed, centrifuge. The obtained solid product is first washed with ethanol 3 times, then washed with 0.1 mol acetic acid solution 10 times, and then dried at 40 ℃ for 12 h to obtain europium metal-organic framework molecularly imprinted polymer (denoted as TB-Eu-MOFs@MIPs).
[0059] (3) Using the post-imprinting modification strategy, 175 mg of the above europium metal-organic framework molecular imprinted polymer, 0.2 mmol of lead bromide, 0.2 mmol of cesium bromide, 1 mmol of 4-bromobutyric acid, and 1 mmol of oleylamine were taken, and 3 mL of N,N-dimethylacetamide and 2 mL of N,N-dimethylpropionamide were added. The mixture was heated and stirred at 70 °C for 10 h to obtain a perovskite quantum dot precursor solution. 2 mmol of rubidium bromide was taken, and 31.25 mL of water was added. The mixture was stirred at room temperature for 30 min to obtain a rubidium bromide solution. Then, 2.5 mL of the perovskite quantum dot precursor solution was injected, and the mixture was heated and stirred at 70 °C for 30 min. After centrifugation, the precipitate was retained to obtain a perovskite quantum dot-europium metal-organic framework molecular imprinted polymer composite material (abbreviated as fluorescent molecular imprinted composite material, denoted as TB-Eu-MOFs@MIPs@CsPbBr3-Rb), which is a kanamycin-responsive perovskite-based ratio fluorescent biomimetic sensing material.
[0060] Example 2 A kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material, the preparation steps of which are as follows: (1) Preparation of europium metal-organic framework materials (TB-Eu-MOFs): The preparation steps are the same as in Example 1.
[0061] (2) 40 mg of europium metal-organic framework material and 0.2 mmol of kanamycin were added to 20 mL of Tris-HCl buffer solution (pH 8.5, 50 mM) and stirred at room temperature for 2 h. After centrifugation, the precipitate was dispersed in 20 mL of ethanol, 0.6 mmol of methacrylic acid was added, and stirred at room temperature for 3 h. Then, 1 mmol of ethylene glycol dimethacrylate and 40 mg of azobisisobutyronitrile were added. The mixture was sonicated to dissolve and disperse evenly. After purging with nitrogen for 15 min, the mixture was sealed and subjected to thermal polymerization in a 65 °C water bath for 2 h. After the reaction was completed, the solid product was centrifuged. The solid product was washed 3 times with ethanol and then 10 times with 0.1 mol acetic acid solution. The product was then dried at 40 °C for 12 h to obtain europium metal-organic framework molecularly imprinted polymer (denoted as TB-Eu-MOFs@MIPs).
[0062] (3) Using the post-imprinting modification strategy, 125 mg of the above europium metal-organic framework molecular imprinted polymer, 0.2 mmol of lead bromide, 0.2 mmol of cesium bromide, 1 mmol of 4-bromobutyric acid, and 1 mmol of oleylamine were added, along with 3 mL of N,N-dimethylacetamide and 2 mL of N,N-dimethylpropionamide. The mixture was heated and stirred at 70 °C for 10 h to obtain a perovskite quantum dot precursor solution. 2 mmol of rubidium bromide was added to 31.25 mL of water and stirred at room temperature for 30 min to obtain a rubidium bromide solution. Then, 2.5 mL of the perovskite quantum dot precursor solution was injected, and the mixture was heated and stirred at 70 °C for 30 min. After centrifugation, the precipitate was retained to obtain a perovskite quantum dot-europium metal-organic framework molecular imprinted polymer composite material (denoted as TB-Eu-MOFs@MIPs@CsPbBr3-Rb), which is a kanamycin-responsive perovskite-based ratio fluorescence biomimetic sensing material.
[0063] Example 3 A kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material, the preparation steps of which are as follows: (1) Preparation of europium metal-organic framework materials (TB-Eu-MOFs): The preparation steps are the same as in Example 1.
[0064] (2) Take 80 mg of europium metal-organic framework material and 0.2 mmol of kanamycin and add them to 20 mL of Tris-HCl buffer solution (pH 8.5, 50 mM). Stir at room temperature for 2 h. After centrifugation, the precipitate is dispersed in 20 mL of ethanol. Add 1.8 mmol of methacrylic acid and stir at room temperature for 3 h. Then add 2.2 mmol of ethylene glycol dimethacrylate and 40 mg of azobisisobutyronitrile. Sonicate to dissolve and disperse evenly. After purging with nitrogen for 15 min, seal and carry out thermal polymerization reaction in a 65 ℃ water bath for 2 h. After the reaction is completed, centrifuge. The obtained solid product is first washed with ethanol 3 times, then washed with 0.1 mol acetic acid solution 10 times, and then dried at 40 ℃ for 12 h to obtain europium metal-organic framework molecularly imprinted polymer (denoted as TB-Eu-MOFs@MIPs).
[0065] (3) Using the post-imprinting modification strategy, 200 mg of the above europium metal-organic framework molecular imprinted polymer, 0.2 mmol of lead bromide, 0.2 mmol of cesium bromide, 1 mmol of 4-bromobutyric acid, and 1 mmol of oleylamine were taken, and 3 mL of N,N-dimethylacetamide and 2 mL of N,N-dimethylpropionamide were added. The mixture was heated and stirred at 70 °C for 10 h to obtain a perovskite quantum dot precursor solution. 2 mmol of rubidium bromide was taken, and 31.25 mL of water was added. The mixture was stirred at room temperature for 30 min to obtain a rubidium bromide solution. Then, 2.5 mL of the perovskite quantum dot precursor solution was injected, and the mixture was heated and stirred at 70 °C for 30 min. After centrifugation, the precipitate was retained to obtain a perovskite quantum dot-europium metal-organic framework molecular imprinted polymer composite material (denoted as TB-Eu-MOFs@MIPs@CsPbBr3-Rb), which is a kanamycin-responsive perovskite-based ratio fluorescence biomimetic sensing material.
[0066] Comparative Example 1 (1) Preparation of europium metal-organic framework materials (TB-Eu-MOFs): The preparation steps are the same as in Example 1.
[0067] (2) 60 mg of europium metal-organic framework material was added to 20 mL of Tris-HCl buffer solution (pH 8.5, 50 mM) and stirred for 2 h. After centrifugation, the precipitate was dispersed in 20 mL of ethanol, 1 mmol of methacrylic acid was added, and the mixture was stirred at room temperature for 3 h. Then, 1.4 mmol of ethylene glycol dimethacrylate and 40 mg of azobisisobutyronitrile were added. The mixture was sonicated to dissolve and disperse evenly. After purging with nitrogen for 15 min, the mixture was sealed and subjected to thermal polymerization in a 65 ℃ water bath for 2 h. After the reaction was completed, the solid product was centrifuged. The solid product was washed 3 times with ethanol and then 10 times with 0.1 mol acetic acid solution. The product was then dried at 40 ℃ for 12 h to obtain europium metal-organic framework non-imprinted polymer (denoted as TB-Eu-MOFs@NIPs).
[0068] (3) Take 175 mg of the above europium metal-organic framework non-imprinted polymer, 0.2 mmol of lead bromide, 0.2 mmol of cesium bromide, 1 mmol of 4-bromobutyric acid, and 1 mmol of oleylamine, add 3 mL of N,N-dimethylacetamide and 2 mL of N,N-dimethylpropionamide, heat and stir at 70 °C for 10 h to obtain a perovskite quantum dot precursor solution; take 2 mmol of rubidium bromide, add 31.25 mL of water, stir at room temperature for 30 min to obtain a rubidium bromide solution, then inject 2.5 mL of the perovskite quantum dot precursor solution, heat and stir at 70 °C for 30 min, centrifuge, retain the precipitate, and obtain a perovskite quantum dot-europium metal-organic framework non-imprinted polymer composite material (abbreviated as fluorescent non-imprinted composite material, denoted as TB-Eu-MOFs@NIPs@CsPbBr3-Rb).
[0069] Comparative Example 2 (1) Take 0.2 mmol of kanamycin and add it to 200 μL of deionized water. After dissolving, disperse it in 20 mL of ethanol. Add 1 mmol of methacrylic acid (MAA) and stir at room temperature for 3 h. Then add 1.4 mmol of ethylene glycol dimethacrylate (EGDMA) and 40 mg of azobisisobutyronitrile. Sonicate to dissolve and disperse evenly. After purging with nitrogen for 15 min to remove oxygen, seal and carry out thermal polymerization reaction in a 65 ℃ water bath for 2 h. After the reaction is completed, centrifuge and wash the obtained solid product with ethanol 3 times, then wash it with 0.1 mol acetic acid solution 10 times. Then dry it at 40 ℃ for 12 h to obtain molecularly imprinted polymers (denoted as MIPs).
[0070] (2) Using the post-imprinting modification strategy, 175 mg of the above molecularly imprinted polymer, 0.2 mmol of lead bromide, 0.2 mmol of cesium bromide, 1 mmol of 4-bromobutyric acid, and 1 mmol of oleylamine were taken, and 3 mL of N,N-dimethylacetamide and 2 mL of N,N-dimethylpropionamide were added. The mixture was heated and stirred at 70 °C for 10 h to obtain a perovskite quantum dot precursor solution. 2 mmol of rubidium bromide was taken, and 31.25 mL of water was added. The mixture was stirred at room temperature for 30 min to obtain a rubidium bromide solution. Then, 2.5 mL of the perovskite quantum dot precursor solution was injected, and the mixture was heated and stirred at 70 °C for 30 min. After centrifugation, the precipitate was retained to obtain a perovskite quantum dot molecularly imprinted polymer composite material (abbreviated as perovskite-based molecularly imprinted polymer, denoted as MIPs@CsPbBr3-Rb).
[0071] Comparative Example 3 (1) Take 0.2 mmol of EuCl3·6H2O and 0.2 mmol of terephthalic acid, add them to a mixed solvent of 14 mL of N,N-dimethylformamide and 6 mL of water, stir at room temperature for 2 h, then purge with nitrogen for 15 min to remove oxygen, transfer to a high-pressure reactor, react at 130 ℃ for 12 h, sonicate for 15 min, centrifuge at 4000 rpm for 10 min, wash three times with a mixed solution of N,N-dimethylformamide and anhydrous ethanol (volume ratio of 14:6), wash twice with anhydrous ethanol, and then dry at 40 ℃ for 12 h to obtain a single-ligand europium metal-organic framework material (denoted as T-Eu-MOFs).
[0072] (2) Take 60 mg of the monoligand europium metal-organic framework prepared in step (1) and 0.2 mmol of kanamycin and add them to 20 mL of Tris-HCl buffer solution (pH 8.5, 50 mM). Stir for 2 h. After centrifugation, the precipitate is dispersed in 20 mL of ethanol. Add 1 mmol of methacrylic acid and stir at room temperature for 3 h. Then add 1.4 mmol of ethylene glycol dimethacrylate and 40 mg of azobisisobutyronitrile. Sonicate to dissolve and disperse evenly. After purging with nitrogen for 15 min, seal and carry out thermal polymerization reaction in a 65 ℃ water bath for 2 h. After the reaction is completed, centrifuge. The obtained solid product is washed 3 times with ethanol and then 10 times with 0.1 mol acetic acid solution. Then dry at 40 ℃ for 12 h to obtain the monoligand europium metal-organic framework molecularly imprinted polymer (denoted as T-Eu-MOFs@MIPs).
[0073] (3) Using the post-imprinting modification strategy, 175 mg of the above-mentioned single-ligand europium metal-organic framework molecular imprinted polymer, 0.2 mmol of lead bromide, 0.2 mmol of cesium bromide, 1 mmol of 4-bromobutyric acid, and 1 mmol of oleylamine were added, along with 3 mL of N,N-dimethylacetamide and 2 mL of N,N-dimethylpropionamide. The mixture was heated and stirred at 70 °C for 10 h to obtain a perovskite quantum dot precursor solution. 2 mmol of rubidium bromide was added to 31.25 mL of water and stirred at room temperature for 30 min to obtain a rubidium bromide solution. Then, 2.5 mL of the perovskite quantum dot precursor solution was injected, and the mixture was heated and stirred at 70 °C for 30 min. After centrifugation, the precipitate was retained to obtain a perovskite quantum dot-single-ligand europium metal-organic framework molecular imprinted polymer composite material (denoted as T-Eu-MOFs@MIPs@CsPbBr3-Rb).
[0074] Test Example 1 Characterization data: Figure 2Fourier transform infrared (FTIR) spectra of TB-Eu-MOFs, TB-Eu-MOFs@MIPs, TB-Eu-MOFs@NIPs, TB-Eu-MOFs@MIPs@CsPbBr3-Rb, and TB-Eu-MOFs@NIPs@CsPbBr3-Rb (TB-Eu-MOFs@NIPs and TB-Eu-MOFs@NIPs@CsPbBr3-Rb were derived from Comparative Example 1, and the remaining samples were derived from Example 1). The 1379 cm⁻¹ in the figure... -1 and 1314 cm -1 Corresponding to BO stretching vibration, 752 cm -1 Corresponding to the CH bending vibration of the aromatic ring, and simultaneously at 1579 cm. -1 and 1426cm -1 The typical absorption peaks at approximately 1728 cm⁻¹ correspond to the asymmetric and symmetric stretching vibrations of the carboxylate group, respectively, confirming the successful synthesis of TB-Eu-MOFs. In the spectra of TB-Eu-MOFs@MIPs and TB-Eu-MOFs@NIPs, the typical absorption peaks at approximately 1728 cm⁻¹ correspond to the asymmetric and symmetric stretching vibrations of the carboxylate group, respectively, confirming the successful synthesis of TB-Eu-MOFs. -1 and 1640cm -1 Characteristic absorption peaks corresponding to C=O and C=C stretching vibrations were observed at 1155 cm⁻¹. -1 and 1259 cm -1 The absorption peak detected at 3500 cm⁻¹ corresponds to the COC stretching vibration. -1 The broad absorption band appearing nearby is due to the OH stretching vibration of the polymer, and a BO characteristic peak (1375 cm⁻¹) associated with TB-Eu-MOFs was also observed. -1 These results confirm the introduction of MAA and EGDMA, as well as the successful synthesis of TB-Eu-MOFs@MIPs and TB-Eu-MOFs@NIPs. Compared with TB-Eu-MOFs@MIPs and TB-Eu-MOFs@NIPs, the curves of TB-Eu-MOFs@MIPs@CsPbBr3-Rb and TB-Eu-MOFs@NIPs@CsPbBr3-Rb both show the C-N bond stretching vibration (1088 cm⁻¹) generated by the zwitterionic ligand formed by oleylamine and 4-bromobutyric acid in CsPbBr3-Rb. -1 ). At 2925 cm -1 and 2852 cm -1 The absorption peaks correspond to the asymmetric and symmetric stretching vibrations of CH in the ligand, respectively. 1660 cm⁻¹ -1 The absorption peak at [value] originates from the NH bending vibration of oleylamine (OLA) on the CsPbBr3-Rb surface. Furthermore, at 3500 cm⁻¹... -1A broad peak appears nearby, caused by the superposition stretching vibration of NH and OH. These results indicate that TB-Eu-MOFs@MIPs@CsPbBr3-Rb and TB-Eu-MOFs@NIPs@CsPbBr3-Rb were successfully synthesized through in-situ growth of CsPbBr3-Rb.
[0075] Figure 3 Scanning electron microscope (SEM) images of TB-Eu-MOFs (A), TB-Eu-MOFs@MIPs (B), and TB-Eu-MOFs@MIPs@CsPbBr3-Rb (C); transmission electron microscope (TEM) images of TB-Eu-MOFs (D), TB-Eu-MOFs@MIPs (E), and TB-Eu-MOFs@MIPs@CsPbBr3-Rb (F); TEM image (G) and high-resolution TEM image (H) of CsPbBr3-Rb; and high-resolution TEM image (I) of TB-Eu-MOFs@MIPs@CsPbBr3-Rb (except for CsPbBr3-Rb, all samples were derived from Example 1. Sample CsPbBr3-Rb was prepared using the method in step (3) of Example 1, except that europium metal-organic framework molecularly imprinted polymer was not added). Figure 4 Scanning electron microscope (SEM) images of TB-Eu-MOFs@NIPs (A) and TB-Eu-MOFs@NIPs@CsPbBr3-Rb (B), and transmission electron microscope (TEM) images of TB-Eu-MOFs@NIPs (C) and TB-Eu-MOFs@NIPs@CsPbBr3-Rb (D) (samples are from Comparative Example 1). It can be seen that TB-Eu-MOFs exhibits a rhombic microcrystalline structure with a porous surface, while the surface of TB-Eu-MOFs@NIPs@CsPbBr3-Rb exhibits a rough morphology. Figure 3 (A) and (F) in the image, which can be attributed to the formation of the imprinted layer. The presence of a clear core-shell structure further confirms the successful synthesis of TB-Eu-MOFs@MIPs@CsPbBr3-Rb through surface modification of the imprinted layer. Scanning electron microscopy images of TB-Eu-MOFs@NIPs (A) and (F) in the image, can be attributed to the formation of the imprinted layer. Figure 4 (A) and transmission electron microscopy (TEM) images Figure 4 The C-PbBr3-Rb structures in the C-PbBr3-Rb matrix exhibit significant structural similarity to TB-Eu-MOFs@MIPs, confirming polymer formation. Furthermore, a significant increase in surface roughness can be observed in TB-Eu-MOFs@MIPs@CsPbBr3-Rb, as shown in the high-resolution transmission electron microscopy (HRTEM) image. Figure 3 In the middle (I) image, small-sized CsPbBr3-Rb particles displaying lattice fringes can be clearly seen, confirming that CsPbBr3-Rb has been successfully incorporated into TB-Eu-MOFs@MIPs.
[0076] Test Example 2 Adsorption performance test (see schematic diagram of test principle) Figure 1 As shown in (C): The TB-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Example 1 (all products obtained with the following raw material amounts: lead bromide 0.2 mmol, cesium bromide 0.2 mmol, 4-bromobutyric acid 1 mmol, oleylamine 1 mmol, and rubidium bromide 2 mmol) was washed seven times with deionized water and reconstituted to 5 mL. 50 μL of the reconstituted solution was placed in a 2 mL centrifuge tube, and 300 μL of different concentrations (0, 0.1, 0.5, 1, 2, 4, 6, 8, 10, 12, 14, 16, 20, 24 mg L) were added to each tube. -1 The KANA standard solution was shaken at room temperature for 2 min, and the fluorescence intensity before and after adsorption was measured using a fluorescence spectrophotometer (excitation wavelength λ = 340 nm, specifically tested at two emission wavelengths of 520 nm and 620 nm). λ em The fluorescence intensity at point () is denoted as F. 520 and F 620 And calculate the ratio between the two, using the ratio before and after adsorption as the ordinate.
[0077] The response curves of TB-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Example 1 to different concentrations of KANA are shown below. Figure 5 As shown in the figure (F) 520 / F 620 )0 is before adsorption, (F 520 / F 620 (After adsorption), it can be seen that the fluorescence intensity of TB-Eu-MOFs@MIPs@CsPbBr3-Rb is higher than that of F. 520 / F 620 )0 / (F 520 / F 620 The concentration of KANA showed a good linear relationship with the concentration of KANA in the range of 0.075-24 μg / mL, with a linear regression equation of y=0.1599x+1.0001 and a coefficient of determination (R²). 2 The limit of detection (LOD) of this sensing material is as high as 0.998. Calculated using the standard formula 3σ / S (where σ represents the standard deviation of the blank solution and S is the slope of the linear calibration curve), the LOD of this sensing material is 22.5 ng / mL, which is lower than the maximum residue limit of KANA stipulated in China (100 μg / kg) and the European Union (150 μg / kg).
[0078] Test Example 3 Adsorption kinetics performance test: The TB-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Example 1, the TB-Eu-MOFs@NIPs@CsPbBr3-Rb prepared in Comparative Example 1, or the MIPs@CsPbBr3-Rb prepared in Comparative Example 2 (all products obtained with the following starting materials: 0.2 mmol lead bromide, 0.2 mmol cesium bromide, 1 mmol 4-bromobutyric acid, 1 mmol oleylamine, and 2 mmol rubidium bromide) were washed 7 times with deionized water and then reconstituted to 5 mL. 50 μL of the reconstituted solution was placed in a 2 mL centrifuge tube, and 300 μL of a 24 mg / L solution was added. -1 The KANA standard solution was shaken at room temperature for 0, 0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 min, respectively, and the fluorescence intensity values before and after adsorption were measured using a fluorescence spectrophotometer (the specific test method and calculation method are the same as in Test Example 2).
[0079] The adsorption kinetic curves of TB-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Example 1, TB-Eu-MOFs@NIPs@CsPbBr3-Rb prepared in Comparative Example 1, and MIPs@CsPbBr3-Rb prepared in Comparative Example 2 are shown below. Figure 6 As shown, after the addition of kanamycin, the fluorescence response of TB-Eu-MOFs@MIPs@CsPbBr3-Rb gradually increased within the first 2 minutes, and the fluorescence intensity ratio tended to stabilize after 2 minutes. Although TB-Eu-MOFs@NIPs@CsPbBr3-Rb showed a similar response trend to TB-Eu-MOFs@MIPs@CsPbBr3-Rb, its fluorescence intensity ratio was significantly lower than that of TB-Eu-MOFs@MIPs@CsPbBr3-Rb. This may be attributed to the presence of special kanamycin imprinting sites in TB-Eu-MOFs@MIPs@CsPbBr3-Rb, which provides a more efficient and convenient way for kanamycin recognition and interaction. Furthermore, it can be seen that MIPs@CsPbBr3-Rb requires a 4-minute equilibration time, indicating that the introduction of TB-Eu-MOFs accelerates the response efficiency of TB-Eu-MOFs@MIPs@CsPbBr3-Rb, thereby giving TB-Eu-MOFs@MIPs@CsPbBr3-Rb superior adsorption performance and higher sensitivity for kanamycin.
[0080] Test Example 4 Selectivity (i.e., adsorption specificity) test: Ribavirin (RBV), tetracycline (TC), streptomycin (STR), gentamicin (GEN), and sisomicin (SIS), which are structurally similar to kanamycin and readily coexist in samples, were selected as investigation targets. The specific steps are as follows: TB-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Example 1, TB-Eu-MOFs@NIPs@CsPbBr3-Rb prepared in Comparative Example 1, or T-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Comparative Example 3 (all products obtained using raw materials of 0.2 mmol lead bromide, 0.2 mmol cesium bromide, 1 mmol 4-bromobutyric acid, 1 mmol oleylamine, and 2 mmol rubidium bromide) were washed 7 times with deionized water and reconstituted to 5 mL. 50 μL of the reconstituted solution was placed in a 2 mL centrifuge tube, and 300 μL of a 24 mg L⁻¹ solution was added to each tube. -1 Kanamycin, ribavirin, tetracycline, streptomycin, gentamicin or sisomicin solution were shaken at room temperature for 2 min, and the changes in fluorescence intensity of different structural analogs on the composite material before and after adsorption were measured by fluorescence spectrophotometer (the specific test method and calculation method are the same as in test example 2).
[0081] Figure 7 The adsorption specificity test results of TB-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Example 1, TB-Eu-MOFs@NIPs@CsPbBr3-Rb prepared in Comparative Example 1, and T-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Comparative Example 3 show that the fluorescence intensity of TB-Eu-MOFs@MIPs@CsPbBr3-Rb to KANA analogs is significantly lower than that of KANA. This high selectivity is attributed to the presence of imprinted holes complementary to KANA inside TB-Eu-MOFs@MIPs@CsPbBr3-Rb. Furthermore, under the same experimental conditions, the order of fluorescence response of the polymers to KANA was: TB-Eu-MOFs@MIPs@CsPbBr3-Rb>T-Eu-MOFs@MIPs@CsPbBr3-Rb>TB-Eu-MOFs@NIPs@CsPbBr3-Rb. This indicates that the boric acid group, as a covalent recognition unit, works synergistically with the non-covalently imprinted site to enhance the precise capture and specific binding ability of TB-Eu-MOFs@MIPs@CsPbBr3-Rb to KANA.
[0082] Test Example 5 Colorimetric testing: The TB-Eu-MOFs@MIPs@CsPbBr3-Rb prepared in Example 1 (all products obtained with the following raw material amounts: lead bromide 0.2 mmol, cesium bromide 0.2 mmol, 4-bromobutyric acid 1 mmol, oleylamine 1 mmol, and rubidium bromide 2 mmol) was washed seven times with deionized water and reconstituted to 5 mL. 50 μL of the reconstituted solution was placed in a 2 mL centrifuge tube, and 300 μL of different concentrations (0.08, 0.125, 0.25, 0.5, 1, 2, 4, 8, 12, 16, 20, 24 mg L) were added to each tube. -1 The KANA standard solution was prepared by shaking at room temperature for 2 minutes and photographed under a 340 nm UV lamp. The color was identified using software. Three sets of parallel experiments were performed (each set of color changes represents a parallel experiment), and the results are as follows: Figure 8 As shown, the ratio fluorescence response is accompanied by a distinct color change, successively changing from green to yellow-green, light pink, and finally to magenta. This enables the controllable adjustment of the ratio fluorescence signal and is used for the visual detection of kanamycin.
[0083] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.
Claims
1. A method for preparing a kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material, characterized in that, Includes the following steps: Europium metal-organic framework material, kanamycin and buffer solution were mixed, stirred and reacted, and then centrifuged. The precipitate after centrifugation was dispersed in solvent 1, methacrylic acid was added, and the mixture was stirred and reacted. Then ethylene glycol dimethacrylate and an initiator were added to carry out a thermal polymerization reaction. After centrifugation, washing and drying, europium metal-organic framework molecularly imprinted polymer was obtained. The europium metal-organic framework molecularly imprinted polymer was mixed with lead bromide, cesium bromide, 4-bromobutyric acid, oleylamine, N,N-dimethylacetamide, and N,N-dimethylpropionamide, and the mixture was heated and stirred to obtain a perovskite quantum dot precursor solution. The perovskite quantum dot precursor solution was mixed with a rubidium bromide solution and the mixture was heated and stirred to obtain a perovskite quantum dot-europium metal-organic framework molecularly imprinted polymer composite material, which is the kanamycin-responsive perovskite-based ratiometric fluorescence biomimetic sensing material.
2. The method for preparing the kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material as described in claim 1, characterized in that, The buffer solution includes a Tris-HCl buffer solution; And / or, solvent 1 includes ethanol; And / or, the initiator includes azobisisobutyronitrile.
3. The method for preparing the kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material as described in claim 1, characterized in that, The ratio of the europium metal-organic framework material, the kanamycin, the methacrylic acid, the ethylene glycol dimethacrylate, and the initiator is 40-80 mg: 0.2 mmol: 0.6-1.8 mmol: 1-2.2 mmol: 40 mg.
4. The method for preparing the kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material as described in claim 1, characterized in that, After mixing europium metal-organic framework material, kanamycin and buffer solution, the reaction temperature was 20-30℃ and the reaction time was 1-3 h. And / or, after adding methacrylic acid, the reaction temperature is 20-30 °C and the reaction time is 2-4 h; And / or, the temperature of the thermal polymerization reaction is 60-70 °C and the time is 2-3 h.
5. The method for preparing the kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material as described in claim 1, characterized in that, The ratio of the europium metal-organic framework molecularly imprinted polymer, the lead bromide, the cesium bromide, the 4-bromobutyric acid, the oleylamine, the N,N-dimethylacetamide, and the N,N-dimethylpropionamide is 125-200 mg:0.2 mmol:0.2 mmol:1 mmol:1 mmol:3 mL:2 mL; And / or, the europium metal-organic framework molecularly imprinted polymer is mixed with lead bromide, cesium bromide, 4-bromobutyric acid, oleylamine, N,N-dimethylacetamide and N,N-dimethylpropionamide and then heated and stirred at a temperature of 65-75 °C for 8-12 h.
6. The method for preparing the kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material as described in claim 1, characterized in that, The volume ratio of the perovskite quantum dot precursor solution to the molar amount of rubidium bromide in the rubidium bromide solution is 2.5 mL: 2 mmol. And / or, the perovskite quantum dot precursor solution is mixed with rubidium bromide solution and then heated and stirred at a temperature of 65-75°C for 20-40 min.
7. The method for preparing the kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material as described in claim 1, characterized in that, The preparation steps of the europium metal-organic framework material include: mixing europium source, terephthalic acid, 2,5-dicarboxyphenylboronic acid and solvent 2, stirring and reacting, and then heating to obtain the europium metal-organic framework material.
8. The method for preparing the kanamycin-responsive perovskite-based ratiometric fluorescent biomimetic sensing material as described in claim 7, characterized in that, The europium source includes EuCl3·6H2O; And / or, the molar ratio of the europium source, the terephthalic acid, and the 2,5-dicarboxyphenylboronic acid is 0.2:0.18:0.02; And / or, the solvent 2 is a mixed solvent of N,N-dimethylformamide and water; And / or, the temperature of the stirring reaction is 20-30 °C, and the time is 1-3 h; And / or, the heating reaction is carried out at a temperature of 120-140 °C for a time of 10-14 h.
9. A kanamycin-responsive perovskite-based ratio fluorescence biomimetic sensing material prepared by the preparation method of any one of claims 1-8.
10. The application of the kanamycin-responsive perovskite-based ratio fluorescence biomimetic sensing material as described in claim 9 in the detection of kanamycin.