A temperature-sensitive molecular imprinting sensitive film, a preparation method thereof and application thereof in a glyphosate detection sensor

Abstract

The application discloses a temperature-sensitive molecular imprinting sensitive film, a preparation method thereof and application thereof in a glyphosate detection sensor, and belongs to the field of optical sensing technology and environmental monitoring. The application forms an imprinting cavity which is highly complementary to a template molecule in size and spatial configuration in a polymer network, realizes specific identification of a target molecule, and solves the problems of complex sample pretreatment and long detection period of the existing glyphosate detection method. The application introduces a temperature-sensitive material PNIPAM, realizes in-situ, non-destructive and reversible release of the template molecule by temperature control, discards the traditional destructive elution mode, avoids causing serious secondary environmental pollution, avoids the problems of swelling and corrosion of the imprinting cavity caused by strong acid or organic solvent, and causes irreversible damage to the structure of the imprinting cavity, which seriously affects the reuse frequency of the sensor and the detection stability.

Description

Technical Field

[0001] This invention relates to a temperature-sensitive molecularly imprinted membrane, its preparation method, and its application in a glyphosate detection sensor. Specifically, it relates to a glyphosate detection method and sensor based on a temperature-responsive molecularly imprinted membrane and fiber evanescent absorption spectroscopy, belonging to the fields of optical sensing technology and environmental monitoring. Background Technology

[0002] Food safety monitoring is of great significance for safeguarding human health and promoting sustainable socio-economic development. Glyphosate, as the most widely used organophosphorus herbicide, poses a serious threat to human health due to its residues. Ingesting food containing excessive glyphosate may cause depression, infertility, and even damage to the central nervous system and other organs. The World Health Organization has set the maximum residue limit for glyphosate in drinking water at 5.32 μM. Therefore, the development of highly sensitive and specific glyphosate detection methods is urgently needed.

[0003] Currently, glyphosate detection technologies mainly include fluorescence methods, high-performance liquid chromatography (HPLC), and spectrophotometry. While these methods offer high detection accuracy, they still suffer from inherent drawbacks such as complex sample pretreatment, long detection cycles, and reliance on large, precision instruments (requiring specialized operators), making them unsuitable for the rapid on-site detection of glyphosate residues in environmental samples such as water and food. In contrast, fiber optic sensing technology, with its advantages of resistance to electromagnetic interference, low cost, and remote monitoring capabilities, shows broad application prospects in the field of environmental monitoring.

[0004] Molecularly imprinted polymer (MIP) technology achieves specific recognition of target molecules by forming imprinted cavities that are highly complementary to template molecules in size, charge, and spatial configuration during cross-linking polymerization. However, traditional MIP materials typically use acidic eluents or chelating agents to remove target molecules, which can cause secondary environmental pollution and damage to the imprinted cavities.

[0005] In recent years, environmentally responsive smart materials, especially thermosensitive polymers, have been able to control their conformation and hydrophilic-hydrophobic balance through temperature changes, enabling the "on-off" switching of the imprinted cavity and the controlled release of template molecules. Poly(N-isopropylacrylamide) (PNIPAM) has become a research hotspot for thermosensitive imprinted materials due to its near-room-temperature lowest critical temperature (LCST), excellent biocompatibility, and environmental friendliness. However, PNIPAM-based materials are still limited by problems such as limited adsorption capacity, insufficient mechanical strength, and difficulty in integration into sensing systems. Therefore, it is essential to provide a glyphosate sensor based on a fiber optic probe using a thermosensitive molecularly imprinted membrane. Summary of the Invention

[0006] To address the problems of complex sample pretreatment, long detection cycle, and high equipment cost in existing glyphosate detection methods, this invention provides a temperature-sensitive molecularly imprinted membrane, its preparation method, and its application in glyphosate detection sensors.

[0007] The technical solution of the present invention: One objective of this invention is to provide a method for preparing a temperature-sensitive molecularly imprinted membrane, the method comprising the following steps: (1) Fe3O4@SiO2 microspheres were prepared by the Stöber hydrolysis method; (2) The surface of Fe3O4@SiO2 microspheres was subjected to vinyl functionalization treatment to obtain Fe3O4@SiO2-C=C microspheres; (3) Photoinitiated free radical polymerization to prepare thermosensitive molecularly imprinted sensitive membranes; Fe3O4@SiO2-C=C microspheres were used as a carrier and dissolved in PBS buffer with crosslinking agent, catalyst, photoinitiator, glyphosate template molecule, functional monomer 4-vinylpyridine, and thermosensitive monomer. After being stirred evenly at room temperature, the mixture was irradiated under a UV lamp and finally placed in deionized water at 50°C for repeated washing. The glyphosate template molecule was removed by inducing temperature change, thus obtaining the Fe3O4@SiO2-MIP sensitive membrane.

[0008] Further specifying, the operation process of step (1) is as follows: Fe3O4 microspheres are dispersed in a mixed solution of ethanol, water and ammonia, and then ethyl silicate is slowly added dropwise. After reacting at room temperature, magnetic separation, washing and drying are performed in sequence to obtain Fe3O4@SiO2 microspheres.

[0009] Furthermore, the volume ratio of Fe3O4 microspheres, ethanol, water, ammonia and ethyl silicate is 1:20~80:1~10:1~10:1~6, and the concentration of ammonia is 25%~28%.

[0010] Further specifying, the operation process of step (2) is as follows: Fe3O4@SiO2 microspheres are dispersed in a mixed solution of ethanol and water, and γ-methacryloyloxypropyltrimethoxysilane is added under N2 protection. The reaction is carried out at room temperature to obtain Fe3O4@SiO2-C=C microspheres with vinyl-modified surface.

[0011] Furthermore, the volume ratio of Fe3O4@SiO2 microspheres, ethanol, water, and γ-methacryloyloxypropyltrimethoxysilane is 1:50~100:10~40:10~40.

[0012] Further specifying, in step (3), the crosslinking agent is N,N'-methylenebisacrylamide, the catalyst is tetramethylethylenediamine, the photoinitiator is diethoxyacetophenone, and the thermosensitive monomer is N-isopropylacrylamide.

[0013] Further specifying, in step (3), the mass ratio of the carrier, catalyst, photoinitiator, template molecule, functional monomer and thermosensitive monomer is 1:0.002~0.05:0.01~0.5:0.02~0.1:0.05~0.2:0.1~0.8.

[0014] The second objective of this invention is to provide a temperature-sensitive molecularly imprinted membrane obtained by the above preparation method.

[0015] The third objective of this invention is to provide an application of the above-mentioned temperature-sensitive molecularly imprinted membrane, specifically for the preparation of a glyphosate detection sensor.

[0016] The fourth objective of this invention is to provide a glyphosate sensor based on a temperature-sensitive molecularly imprinted fiber probe. Specifically, the sensor is based on an MMF-TCF-MMF cascaded fiber structure with an expanded waist design, and the surface of the sensing probe is uniformly coated with the aforementioned temperature-sensitive molecularly imprinted sensitive film.

[0017] Beneficial effects: This invention integrates the advantages of molecular imprinting technology, smart responsive materials, and fiber optic sensing, proposing a fiber optic sensor based on a temperature-responsive imprinted sensing film for real-time online detection of glyphosate in aquatic environments and agricultural products. Compared with existing technologies, it has the following advantages: (1) This invention introduces poly(N-isopropylacrylamide) (PNIPAM) as a thermistor material. Utilizing PNIPAM's lowest critical dissolution temperature (LCST, approximately 32°C) in aqueous solution, when the ambient temperature is below the LCST, the polymer chains are in an extended conformation, and the imprinted cavity is in an "open" state, allowing for the specific binding of glyphosate molecules. When the ambient temperature rises above the LCST, the polymer chains collapse from the extended conformation to a spherical conformation, the hydrogel network shrinks, and the imprinted cavity changes to a "closed" state, thereby releasing glyphosate molecules in situ and rapidly. Furthermore, upon cooling to room temperature, the hydrogel re-swells, and the imprinted cavity returns to its initial configuration, achieving reversible regeneration of the sensor.

[0018] (2) This invention achieves specific recognition of target molecules by forming imprinted cavities in polymer networks that are highly complementary to template molecules in size and spatial configuration. Furthermore, by introducing the thermosensitive material PNIPAM, it achieves in-situ, non-destructive, and reversible release of template molecules using temperature control. This eliminates the traditional destructive elution mode, avoids serious secondary environmental pollution, and also avoids the problem of irreversible damage to the imprinted cavity structure caused by the swelling and corrosion of the imprinted cavity by strong acids or organic solvents, which seriously affects the number of times the sensor can be reused and the detection stability. This invention achieves the synergistic unity of selective recognition and non-destructive regeneration.

[0019] (3) This invention employs a waist-expanding MMF-TCF-MMF (multimode fiber-fine core fiber-multimode fiber) cascaded fiber structure. Utilizing the waist-expanding design of the multimode fiber (62.5 μm core diameter) and the fine core fiber (5 μm core diameter), a stronger evanescent field is generated at the fiber core-cladding interface. Furthermore, the fiber structure undergoes multiple re-discharge treatments to form a spherical waist-expanding structure (electric sphere), allowing the light field energy to penetrate more fully into the fiber cladding through the spherical effect, significantly enhancing the interaction strength between the evanescent field and the sample. In addition, the core diameter difference between MMF and TCF (62.5 μm vs 5 μm) creates asymmetric mode field coupling, effectively exciting more higher-order modes and further extending the effective interaction distance between light and the analyte. This, combined with the thermosensitive molecularly imprinted sensitive membrane, results in a detection sensitivity of 0.17 nm / μM for glyphosate, with a detection limit as low as 0.38 μM.

[0020] This invention employs fiber optic evanescent wave sensing technology, utilizing the direct interaction between the evanescent field generated when light propagates through an optical fiber and the sample under test. Quantitative analysis of glyphosate is achieved by detecting the wavelength shift in the interference spectrum. This method requires no complex sample pretreatment, has a short detection cycle, and uses a small, low-cost instrument, enabling in-situ, real-time, and online monitoring of glyphosate in aquatic environments.

[0021] (4) This invention introduces Fe3O4 magnetic microspheres as a carrier, utilizing the high specific surface area of ​​Fe3O4 microspheres to provide more binding sites in the imprinted cavity, significantly improving the adsorption capacity for glyphosate; and uses Fe3O4 microspheres as a rigid carrier to enhance the mechanical strength of the imprinted film, solving the problem of easy breakage when the thermosensitive material is formed alone; at the same time, the unique superparamagnetism of Fe3O4 microspheres endows the imprinted film with magnetic response characteristics, which can be achieved by applying an external magnetic field to realize the rapid separation and replacement of the sensitive film, providing convenience for the separation, recycling and regeneration of the sensor, and laying the foundation for the functional integration and recycling of the device. It effectively solves the bottleneck problems that PNIPAM-based thermosensitive imprinted materials still face in practical applications, such as limited adsorption capacity, poor mechanical strength and difficulty in uniform and stable film formation on the surface of optical fibers, although they have unique advantages in controlled release.

[0022] Furthermore, the Stöber hydrolysis method was used to coat the surface of Fe3O4 microspheres with a SiO2 layer containing a high-density, uniformly distributed silanol groups (Si-OH). This avoids the problem of limited and unevenly distributed active groups on the Fe3O4 microsphere surface, which makes it difficult to form stable and high-density chemical bonds with subsequent functional monomers or crosslinking agents. The silanol groups coated on the Fe3O4 microsphere surface are ideal chemically active sites that can react efficiently with silane coupling agents. This facilitates the subsequent introduction of vinyl (C=C) double bonds that can participate in the polymerization reaction on the Fe3O4@SiO2 microsphere surface, providing a strong and uniform chemical connection basis for the subsequent photoinitiated free radical polymerization to prepare the MIP layer. This ensures that the MIP layer can be stably and densely coated on the surface of the magnetic microspheres, rather than being a simple physical adsorption.

[0023] Furthermore, the abundant silanol groups on the surface of the SiO2 layer give it good hydrophilicity, which can effectively inhibit the non-specific adsorption of biomacromolecules such as proteins and lipids. At the same time, it significantly improves the dispersion stability of the hydrophobic Fe3O4 microspheres in the aqueous system (PBS buffer), avoids aggregation, and allows the Fe3O4@SiO2 microspheres to be more uniformly dispersed in the polymerization reaction solution and maintain a high specific surface area in the final sensitive film, providing more effective binding sites for glyphosate molecules.

[0024] In addition, the SiO2 layer also protects the Fe3O4 microspheres from chemical corrosion in acidic or oxidizing environments, improves chemical stability, avoids the weakening or loss of magnetism due to chemical corrosion, and prevents the release of iron ions from interfering with detection. This significantly improves the long-term chemical stability and structural integrity of the magnetic microspheres during preparation and use.

[0025] (5) This invention employs room-temperature photoinitiated polymerization technology to achieve controllable growth of the imprinted film on the fiber surface. It also solves the problem that traditional thermally initiated polymerization may affect the activity of the temperature-sensitive monomer, and that the high-temperature environment during thermally initiated polymerization may cause PNIPAM to undergo a conformational change before the polymerization reaction is complete, thus affecting the regularity and recognition performance of the imprinted cavity. Specifically, this invention uses diethoxyacetophenone (DEAP) as a photoinitiator to complete the free radical polymerization reaction at room temperature under ultraviolet light irradiation (100W, 30min), ensuring that PNIPAM maintains its extended conformation throughout the polymerization process, which is beneficial for forming a regular imprinted cavity. Simultaneously, photoinitiated polymerization can be carried out in situ on the fiber surface. By controlling the ultraviolet light irradiation area and irradiation time, precise and controllable growth of the imprinted film in the fiber sensing area can be achieved. Furthermore, the initiation polymerization reaction is fast, avoiding potential thermal damage to the temperature-sensitive monomer and template molecules caused by prolonged heating.

[0026] (6) This invention uses 4-vinylpyridine as a functional monomer. Utilizing the characteristic that the nitrogen atom on its pyridine ring can become positively charged through protonation, it generates a strong electrostatic attraction between positive and negative charges before polymerization, serving as a specific binding site to form a pre-assembled complex with negatively charged glyphosate in solution. Simultaneously, the pyridine nitrogen of 4-VP can form a hydrogen bond network with the oxygen atoms in the carboxyl and phosphonic acid groups and the hydrogen atoms in the amine groups of glyphosate. During polymerization, 4-VP participates in free radical polymerization through its vinyl group (C=C), covalently linking to a rigidly cross-linked polyacrylamide gel network. This results in the 4-VP molecules pre-assembled with glyphosate being frozen within the polymer after polymerization, thus forming a specific recognition site. When the glyphosate molecules are removed by temperature change, a cavity remains in the polymer network that is highly complementary to the glyphosate molecule in size, shape, and charge distribution. This cavity is filled with positively charged pyridinium groups and hydrogen bond donors / acceptors provided by 4-VP. When the sensor is immersed in a glyphosate solution, these specific sites can selectively capture glyphosate again through electrostatic attraction and hydrogen bonding, thereby achieving highly specific recognition. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the glyphosate sensing probe based on a temperature-sensitive molecularly imprinted fiber optic probe prepared according to the present invention. Figure 2 This is a schematic diagram of the connection of the glyphosate sensor system based on a temperature-sensitive molecularly imprinted fiber optic probe prepared in this invention. Figure 3 The spectrum of a glyphosate sensor based on a thermosensitive molecularly imprinted fiber optic probe varies with glyphosate concentration. Figure 4 A standard curve of glyphosate concentration versus wavelength shift; Figure 5 The results are from the sensor stability test. Figure 6 This is the result of the sensor repeatability test. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0029] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the materials, reagents, methods, and instruments used are all conventional materials, reagents, methods, and instruments in the art, and can be obtained commercially by those skilled in the art.

[0030] Example 1 (I) Preparation of temperature-sensitive molecularly imprinted sensitive membrane, the specific process is as follows: (1) Fe3O4@SiO2 microspheres were prepared by the Stöber hydrolysis method; Specifically, 1 mL of Fe3O4 microspheres (average particle size of 50-300 nm) were dispersed in a mixed solution of 50 mL of ethanol, 5 mL of water and 5 mL of ammonia (mass concentration of 25%), and then 3 mL of ethyl silicate was slowly added dropwise. After reacting at room temperature, magnetic separation was performed, and the microspheres were washed with 50 °C hot water as the washing solution. The microspheres were then freeze-dried at -60 °C to obtain Fe3O4@SiO2 microspheres.

[0031] (2) The surface of Fe3O4@SiO2 microspheres was subjected to vinyl functionalization treatment to obtain Fe3O4@SiO2-C=C microspheres; Specifically, 1g of Fe3O4@SiO2 microspheres were dispersed in a mixed solution of 75mL ethanol and 25mL water. Under N2 protection, 25mL of γ-methacryloyloxypropyltrimethoxysilane was added, and the reaction was carried out at room temperature to obtain Fe3O4@SiO2-C=C microspheres with vinyl-modified surfaces.

[0032] (3) Photoinitiated free radical polymerization to prepare thermosensitive molecularly imprinted sensitive membranes; Specifically, 0.3 g of Fe3O4@SiO2-C=C microspheres were used as a carrier and dissolved in 5 mL of PBS buffer (pH 7.4) with 7.7 mg of crosslinking agent N,N'-methylenebisacrylamide, 10 μL of catalyst tetramethylethylenediamine, 100 μL of photoinitiator diethoxyacetophenone, 20 mg of template molecule glyphosate, 30 mg of functional monomer 4-vinylpyridine, and 0.1 g of thermosensitive monomer N-isopropylacrylamide. After stirring at room temperature, a polymerization precursor was obtained. The polymerization precursor was irradiated under a UV lamp for 30 s and then placed in deionized water at 50 °C for repeated washing. The template molecule glyphosate was removed by temperature change to obtain the Fe3O4@SiO2-MIP sensitive membrane.

[0033] (II) Fabrication of a glyphosate sensing probe based on a temperature-sensitive molecularly imprinted fiber optic probe (1) Use a fiber fusion splicer to fusion the single-mode fiber SMF and MMF (core diameter 62.5μm), and perform multiple re-discharge treatments on the MMF part to form a spherical SMF-MMF. Then, fusion the spherical SMF-MMF with TCF (core diameter 5μm) to form an SMF-MMF-TCF structure based on waist expansion.

[0034] (2) Repeat the above operation to merge and splice the two sections of the structure to finally obtain the MMF-TCF-MMF fiber structure based on the waist expansion.

[0035] (3) The polymer precursor prepared in (I) is uniformly coated onto the above optical fiber structure, irradiated under a UV lamp for 30 s, placed in deionized water, and heated to 50 °C to induce the removal of the glyphosate template molecule through temperature change. The mixture is washed three times, each time for 5 min, to obtain a temperature-sensitive glyphosate molecular imprinted sensitive film on the surface of the optical fiber structure. This film serves as a functionalized sensing probe, such as... Figure 1 As shown.

[0036] (III) Assembling the sensor system like Figure 2 As shown, the sensing system includes an amplified spontaneous emission source (ASE) and an OSA spectrometer. The light output from the ASE is coupled into the sensing probe via a transmission fiber, and its interference spectrum is recorded by the OSA.

[0037] (iv) Detection methods for glyphosate The sensing probe is placed in a sample cell containing glyphosate, and measurements are taken under constant temperature conditions. By recording the wavelength shift of the interference spectrum, the glyphosate molecule can be quantitatively detected.

[0038] Specifically, the sensing probe was placed in glyphosate standard solutions of 0 μM, 1 μM, 2 μM, 10 μM, 20 μM, 40 μM, 60 μM, 100 μM, and 200 μM, respectively, and the interference spectra at each concentration were recorded at room temperature. The test results are as follows: Figure 3 As shown, by Figure 3 It is known that with increasing glyphosate concentration, the interference spectrum exhibits a significant redshift, with a maximum wavelength shift of 34.82 nm in the 0–200 μM concentration range. This phenomenon is attributed to the specific binding between the imprinted cavity in the sensitive film and glyphosate molecules, leading to a change in the effective refractive index of the sensor probe surface, which in turn shifts the interference wavelength towards longer wavelengths. When the glyphosate concentration exceeds 200 μM, the imprinted cavity in the sensitive film tends to saturate, and the sensor response no longer changes significantly with increasing concentration. Further analysis of the relationship between the interference spectrum shift and glyphosate concentration (e.g., ...) is crucial. Figure 4 As shown in the figure, the sensitivity of the functionalized sensor is 0.17 nm / μM. Furthermore, the response times of this sensor probe for 0 μM and 200 μM glyphosate solutions are approximately 180 s and 270 s, respectively.

[0039] The limit of detection (LOD) is the lowest concentration of a target substance that a sensor can detect. It is calculated using the following formula: Where σ is the standard deviation of the spectral shift of the blank sample, and k is the sensitivity of the sensor.

[0040] Place the sensing probe in a blank solution (0 μM), and after the spectrum stabilizes, record the wavelength shift of the interference spectrum 10 times consecutively. Figure 5As shown, the calculated standard deviation σ of the spectral drift is 0.0214 nm, indicating stable detection stability. Combined with the sensitivity k = 0.17 nm / μM, the calculated detection limit of the sensor designed in this invention is 0.38 μM. This detection limit is far below the maximum residue limit of glyphosate in drinking water set by the World Health Organization (5.32 μM), fully meeting the requirements for trace glyphosate detection in actual environmental samples.

[0041] Further characterization of the sensor's reusability was conducted. Specifically, after each measurement, the sensor probe was placed in deionized water, heated to 50°C to induce glyphosate production through temperature changes, and washed repeatedly three times, each time for 5 minutes, before the next measurement cycle. After 10 cycles, no significant performance loss was observed. Figure 6 As shown.

[0042] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A method for preparing a temperature-sensitive molecularly imprinted sensitive membrane, characterized in that, include: (1) Fe3O4@SiO2 microspheres were prepared by the Stöber hydrolysis method; (2) The surface of Fe3O4@SiO2 microspheres was subjected to vinyl functionalization treatment to obtain Fe3O4@SiO2-C=C microspheres; (3) Photoinitiated free radical polymerization to prepare thermosensitive molecularly imprinted sensitive membranes; Fe3O4@SiO2-C=C microspheres were used as a carrier and dissolved in PBS buffer at pH 7 with a crosslinking agent, catalyst, photoinitiator, glyphosate template molecule, functional monomer 4-vinylpyridine, and thermosensitive monomer. After being stirred evenly at room temperature, the mixture was irradiated under a UV lamp and finally placed in deionized water at 50°C for repeated washing. The glyphosate template molecule was removed by inducing temperature change, thus obtaining the Fe3O4@SiO2-MIP sensitive membrane.

2. The preparation method according to claim 1, characterized in that, The operation process of step (1) is as follows: Fe3O4 microspheres are dispersed in a mixed solution of ethanol, water and ammonia, and then ethyl silicate is slowly added dropwise. After the reaction at room temperature, magnetic separation, washing and drying are performed in sequence to obtain Fe3O4@SiO2 microspheres.

3. The preparation method according to claim 2, characterized in that, The volume ratio of Fe3O4 microspheres, ethanol, water, ammonia and ethyl silicate is 1:20~80:1~10:1~10:1~6, and the concentration of ammonia is 25%~28%.

4. The preparation method according to claim 1, characterized in that, The operation process of step (2) is as follows: Fe3O4@SiO2 microspheres are dispersed in a mixed solution of ethanol and water, and γ-methacryloyloxypropyltrimethoxysilane is added under N2 protection. The reaction is carried out at room temperature to obtain Fe3O4@SiO2-C=C microspheres with vinyl-modified surface.

5. The preparation method according to claim 4, characterized in that, The volume ratio of Fe3O4@SiO2 microspheres, ethanol, water and γ-methacryloyloxypropyltrimethoxysilane is 1:50~100:10~40:10~40.

6. The preparation method according to claim 1, characterized in that, In step (3), the crosslinking agent is N,N'-methylenebisacrylamide, the catalyst is tetramethylethylenediamine, the photoinitiator is diethoxyacetophenone, and the thermosensitive monomer is N-isopropylacrylamide.

7. The preparation method according to claim 1, characterized in that, In step (3), the mass ratio of the carrier, catalyst, photoinitiator, template molecule, functional monomer and thermosensitive monomer is 1:0.002~0.05:0.01~0.5:0.02~0.1:0.05~0.2:0.1~0.

8.

8. A thermosensitive molecularly imprinted sensitive membrane obtained by the preparation method according to any one of claims 1 to 7.

9. An application of the temperature-sensitive molecularly imprinted sensitive membrane according to claim 8, characterized in that, Used to prepare a glyphosate detection sensor.

10. A glyphosate sensor based on a temperature-sensitive molecularly imprinted fiber optic probe, characterized in that, Based on the expansion design of the MMF-TCF-MMF cascaded fiber structure, the surface of the sensing probe is uniformly coated with the temperature-sensitive molecularly imprinted sensitive film as described in claim 8.

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