Preparation method and application of fluorescent COF based on assistance of sound waves and light waves

Abstract

The invention discloses a preparation method and application of fluorescent COF based on assistance of sound waves and light waves, and belongs to the technical field of adsorption separation functional materials. The technical problem to be solved is to provide an efficient preparation method of fluorescent COF aiming at the current situation that the preparation method of the COF in the prior art is low in synthesis process efficiency and harsh in reaction condition. According to the technical scheme, the preparation method of the fluorescent COF based on assistance of the sound waves and the light waves comprises the steps that (1) TAPB, DVA, DMTA and a catalyst are dissolved in water and mixed, S-[C = C] X COF is obtained through purification after ultrasonic irradiation treatment, and X is the proportion of the mass of DVA in the sum of the mass of DVA and the mass of DMTA; x is selected from 0 < X < 1; and (2) dissolving the S-[C = C] X COF obtained in the step (1), a sulfydryl monomer and a photoinitiator in a solvent, mixing, carrying out ultraviolet radiation treatment, and purifying to obtain the fluorescent COF.

Description

Technical Field

[0001] This invention relates to the field of adsorption and separation functional materials technology, specifically to a method for preparing and applying a fluorescent COF based on acoustic and optical wave assistance. Background Technology

[0002] Covalent organic frameworks (COFs) are a class of crystalline porous polymers in which organic units are integrated into a highly ordered structure through polymerization. They have attracted considerable attention due to their applications in catalysis, adsorption, separation, chemical sensing, drug delivery, and energy storage and production. The traditional and most common method for synthesizing COFs is solvothermal synthesis, but this typically requires high reaction temperatures, a high-pressure, oxygen-free closed environment, long reaction times, and toxic organic solvents. [1-2] These drawbacks limit the application of synthesized COF.

[0003] Other synthesis methods include room temperature synthesis, mechanical grinding synthesis, and microwave synthesis. [3-4] These methods can accelerate solvothermal synthesis or avoid complex synthesis conditions. However, they still cannot avoid problems such as the use of large amounts of toxic organic solvents and catalysts, and the crystallinity and porosity of the produced COFs are limited, thus restricting their practical applicability.

[0004] 1. Geng, KY et al. Covalent organic frameworks: design, synthesis, and functions. Chem. Rev. 120, 8814-8933 (2020). 2. Y. Su, M. Qin, J. Kong, Q. Zhai, D. Yuan, Z. Liu and Y. Fang, Adv. Funct. Mater., 34, 2400433 (2024). 3. Matsumoto, M. et al. Rapid, low temperature formation of imine-linked covalent organic frameworks catalyzed by metal triflates. J. Am. Chem.Soc. 139, 4999-5002 (2017). 4. BP Biswal, S. Chandra, S. Kandambeth, B. Lukose, T. Heineand R. Banerjee, J. Am. Chem. Soc., 135, 5328-5331(2013). Relevant patent documents retrieved: This document, published in China (CN119016036A) on November 26, 2024, discloses a controllable preparation method for cross-wrinkled COF nanocapsules and their application in the selective separation of gold. The method uses 1,3,5-tris(4-aminophenyl)benzene (TAPB) and 2,5-divinyl terephthalaldehyde (Dva) as monomers, first crystallizing at room temperature, then recrystallizing at high temperature, followed by the controllable preparation of cross-wrinkled COF nanocapsule adsorbents (CR-COF@DMSA) using racemic-2,3-dimercapsulosic acid (DMSA) as the functional monomer. This method not only achieves controllable morphology but also significantly improves adsorption performance. This document has significant economic value in the field of precious metal recycling, effectively addressing the waste of precious metal resources and environmental pollution caused by electronic waste, while also providing new ideas for designing low-cost, high-performance adsorbents.

[0005] This document, published in China (CN117599617A) on February 27, 2024, discloses a chiral covalent organic framework composite membrane prepared by in-situ growth and its applications. The document is titled [NALC]. X -TAPB-DVA COF S As a functionalized material, a chiral covalent organic framework composite membrane was prepared by a secondary in-situ growth method using terephthalaldehyde (PAD) as the linker and 1,3,5-tris(4-aminophenyl)benzene (TAPB) as the nucleation site. This chiral covalent organic framework composite membrane can resolve enantiomers of mandelic acid, warfarin, tazoline, and ibuprofen, exhibiting a wide resolution range and stable resolution performance.

[0006] The prior art represented by the aforementioned documents has at least the following unresolved technical problems or defects: (1) The synthesis process is inefficient and takes too long. The relevant evidence is: CN119016036A, which uses a multi-step crystallization process that takes a lot of time. The two-step crystallization strategy of "room temperature crystallization (2-10h) + high temperature recrystallization (24-72h)" has a single-step reaction time of up to 72h and a total time of more than 26h. (2) The functional monomer has limited adaptability. The relevant evidence is: Publication No. CN119016036A. This literature only uses DMSA as a functional monomer, which depends on the reaction between thiol and COF. The functional site type is fixed (only containing carboxyl and thiol groups), and it cannot flexibly expand other active groups.

[0007] In solving the above problems or overcoming the above defects, the present invention encountered the following difficulties and obstacles: When sound or light irradiation instruments are operated continuously, the temperature requirements are affected (mostly due to the temperature rise caused by continuous operation), and it is necessary to wait for the temperature to drop to room temperature or to take turns using several instruments. Summary of the Invention

[0008] The purpose of this invention is to provide: A method for preparing fluorescent COF based on acoustic and optical wave assistance, and related technologies, to solve technical problems such as improving synthesis efficiency, improving the stability of fluorescence performance, and increasing fluorescence intensity, or combinations thereof.

[0009] Terminology Explanation: Unless otherwise defined, all technical terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this subject matter pertains. Unless otherwise stated, all patents, patent inventions, and disclosures cited throughout this document are incorporated herein by reference in their entirety. Where multiple definitions exist for terms herein, the definitions provided in this chapter shall prevail.

[0010] It should be understood that the above brief description and the following detailed description are exemplary and for illustrative purposes only, and do not limit the subject matter of the invention in any way. In this invention, the singular is used in conjunction with the plural unless otherwise specifically stated. It should also be noted that, unless otherwise stated, the use of “or” or “or” means “and / or”. Furthermore, the use of the term “comprising” and other forms such as “including,” “containing,” and “contains” are not limiting.

[0011] Definitions of standard chemical terms can be found in the references "Fluorescent Covalent Organic Frameworks" (2023), "Introduction to Grid Chemistry: Metal-Organic Frameworks and Covalent Organic Frameworks", and "Covalent Organic Frameworks: Design, Synthesis, and Applications".

[0012] Unless otherwise stated, conventional methods within the scope of the art, such as adsorption capacity assessment, infrared spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis, shall be used.

[0013] Unless specifically defined herein, the use of all commercially available products herein employs standard techniques. For example, it may be carried out using the manufacturer's instructions for use with the kit, or in accordance with methods known in the art or the description of this invention. The techniques and methods described herein can generally be implemented according to conventional methods well known in the art, based on the descriptions in the various summary and more specific documents cited and discussed in this specification.

[0014] The term "covalent organic framework (COF)" as used in this article refers to a crystalline porous polymer material composed of organic building blocks connected by reversible covalent bonds. It has a regular pore structure, high specific surface area and designable topology, and has application value in fields such as fluorescence sensing, catalysis and gas storage. Functional customization can be achieved by controlling the type of building blocks and reaction conditions during the preparation process.

[0015] The term "TAPB" as used in this article refers to 1,3,5-tris(4-aminophenyl)benzene, with the chemical formula C2. 24 H 21 N3, CAS number 118727-34-7, is an aromatic polyamine monomer with a triphenylamine structure. Its molecule contains three active amino groups and can be used as a core building block in the preparation of COF. It can be used to construct COF materials with three-dimensional or two-dimensional topological structures by undergoing Schiff base condensation reaction with aldehyde monomers.

[0016] As used in this article, the term "DVA" refers to 2,5-divinyl-1,4-phenylenedialdehyde, with the chemical formula C64-. 12 H 10 O2, CAS number 2065232-74-6, is an aromatic monomer containing a dialdehyde group and a divinyl group. The aldehyde group can serve as a condensation reaction site to construct the main chain backbone of a COF with an amino monomer, while the vinyl group can serve as an active site for subsequent functionalization modification to introduce fluorescent groups or other functional groups.

[0017] As used in this article, the term "DMTA" refers to 2,5-dimethoxybenzene-1,4-dicarboxaldehyde, with the chemical formula C9H12H2O. 13 N, CAS number 99-97-8, is an aromatic tertiary amine compound that is often used as a reaction catalyst or co-catalyst in the preparation of COF. It can promote the aldehyde-amine condensation reaction, improve the crystallinity and nucleation efficiency of COF materials, and can also be used as a co-initiator for free radical polymerization.

[0018] The term "thiol monomer" used in this article refers to organic monomers containing thiol (-SH) functional groups in their molecular structure. These monomers can be introduced into the COF backbone through "click" reactions, thio-ene addition reactions, etc., to regulate the surface properties of COF, functionalize pores, or enhance fluorescence performance. Common thiol monomers include mercaptobenzoic acid and mercaptoaniline.

[0019] The terms "methanol" and "MeOH" used in this article refer to: a polar protic solvent that is commonly used as a reaction solvent, washing solvent, or dispersion medium in the preparation of COF. It can dissolve most organic monomers and promote the uniform dispersion and reaction of building blocks.

[0020] The term "Cys" used in this article refers to cysteine, a natural amino acid containing thiol and amino groups. In the preparation and functionalization of COF, it can be used as a small molecule modifier to bind to the COF backbone through thiol or amino groups, thereby endowing the material with biocompatibility or specific recognition properties.

[0021] The term "photoinitiator I2959" as used in this article refers to a commercially available photoinitiator with the chemical name 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone. In the preparation of COF, it can generate free radicals under ultraviolet light irradiation, initiating the polymerization reaction of unsaturated groups such as vinyl groups and acrylate groups, and is used for the post-crosslinking modification or surface functionalization of COF.

[0022] The term "click reaction" used in this article refers to a class of organic synthesis reactions characterized by high efficiency, high selectivity, and mild reaction conditions. In the field of COF preparation, commonly used click reactions include copper-catalyzed azido-alkynyl cycloaddition reactions (CuAAC), thio-alkene addition reactions, Diels-Alder reactions, etc., which can be used for post-modification of the COF skeleton or site-specific incorporation of functional monomers to achieve functionalized customization of COF materials.

[0023] The term "deionized distilled water" or "DDW" as used in this article refers to: a type of high-purity water that has undergone distillation and ion exchange treatment, with extremely low ion content. In COF preparation, it is often used as a washing solvent to remove residual monomers, catalysts, or impurities from the reaction, or as a dispersion medium for aqueous system reactions.

[0024] The term "cavitation effect" used in this article refers to the phenomenon in which a large number of tiny bubbles (cavitation bubbles) are formed inside a liquid medium due to periodic pressure changes (such as ultrasonic oscillation, hydraulic disturbance, etc.). These bubbles undergo a dynamic process of formation, growth, contraction and collapse. At the moment of bubble collapse, local high temperature, high pressure, strong shock wave and microjets are generated in a very small space, which in turn produce physical or chemical effects on the surrounding medium or material surface.

[0025] The term "ultrasonic irradiation treatment" as used in this article refers to a physical treatment method that uses ultrasonic waves of a specific frequency and power to transmit acoustic energy to a target object through a medium (such as a liquid, solid, or gas), inducing physical and chemical changes such as mechanical vibration, cavitation effect, thermal effect, or chemical effect, thereby achieving technical goals such as material modification, biological sample processing, and pollutant degradation.

[0026] The term "ultraviolet irradiation treatment" as used in this article refers to a physical treatment method that uses ultraviolet light (UV) in a specific wavelength range as a radiation source to apply ultraviolet light energy to a target object (such as materials, microorganisms, liquid samples, etc.), thereby inducing changes in the physical, chemical, or biological properties of the target object through photochemical, photothermal, or ionization effects, in order to achieve technical objectives such as disinfection and sterilization, material modification, and surface activation.

[0027] In a first aspect, the present invention provides: a method for preparing fluorescent COF based on acoustic and optical wave assistance, comprising the steps of: (1) S-[C=C] X Preparation of COF: TAPB, DVA, DMTA, and the catalyst were dissolved in water and mixed, then purified after ultrasonic irradiation to obtain S-[C=C]. X Preparation of COF, wherein X represents the proportion of the mass of DVA in the sum of the masses of DVA and DMTA; X is selected from 0 < X ​​< 1; (2) S-[Y] X Preparation of COF: The S-[C=C] obtained in step (1) X COF was dissolved in a solvent and mixed with a thiol monomer and a photoinitiator. After purification by ultraviolet irradiation, the fluorescent COF was obtained, denoted as S-[Y]. X COF, where Y represents a thiol monomer.

[0028] The technical features include: TAPB, DVA, DMTA, catalyst, ultrasonic irradiation, ultraviolet irradiation, thiol monomer, photoinitiator, etc.

[0029] Preferably, the ratio of the molar mass of TAPB in step (1) to the sum of the molar masses of DVA and DMTA is 2:3; The catalyst in step (1) is selected from at least one of formic acid, acetic acid, trifluoroacetic acid and p-toluenesulfonic acid; The catalyst is preferably acetic acid; The mixing method described in step (1) includes, but is not limited to, at least one of ultrasonic dispersion mixing, magnetic stirring mixing, grinding and mixing, and vortex oscillation mixing. The preferred mixing method is vortex oscillation mixing. The irradiation intensity of the ultrasonic irradiation treatment in step (1) is selected from 100-1000 W; The preferred irradiation intensity for the ultrasonic irradiation treatment is 560-1000 W; The preferred irradiation intensity for the ultrasonic irradiation treatment is 840 W; The duration of the ultrasonic irradiation treatment in step (1) is 20-60 min; The preferred duration of the ultrasonic irradiation treatment is 50 min; Preferably, the range of X in step (1) is 0.5 ≤ X < 1; More preferably, X is 0.66; The purification process described in step (1) includes, but is not limited to, washing and drying processes; Furthermore, the solvent for washing is preferably at least one selected from acetone, dichloromethane, water, tetrahydrofuran, ethanol, and methanol; The washing solvent is preferably a combination of acetone, dichloromethane and methanol, used for washing in sequence; Furthermore, the drying method includes, but is not limited to, at least one of vacuum drying, freeze drying, hot air circulation drying, combined vacuum and freeze drying, and supercritical drying; The preferred drying method is vacuum drying; The drying method is further preferably vacuum drying at a temperature of 30-80 °C for 6-24 h.

[0030] The drying method is further preferably vacuum drying at a temperature of 60 °C for 12 h.

[0031] The solvent in step (2) is selected from at least one of methanol, ethanol, N,N-dimethylformamide, acetone and isopropanol; The solvent used in step (2) is preferably methanol; Wherein, the thiol monomer in step (2) is selected from at least one of Cys, mercaptopropionic acid, 1-mercapto-2-propanol, 1,2-ethylenedithiol and trimethylolpropane tris(3-mercaptopropionate); The thiol monomer is preferably at least one of Cys and mercaptopropionic acid; The thiol monomer is further preferably Cys; Preferably, the Cys is an aqueous solution of Cys; More preferably, the concentration of the Cys aqueous solution is selected from 28-112 mg / mL. -1 ; More preferably, the concentration of the Cys aqueous solution is 56 mg / mL. -1; The photoinitiator in step (2) includes, but is not limited to, at least one of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone (I2959), 1-hydroxycyclohexylphenyl ketone (I184), 2,2-dimethoxy-2-phenylacetophenone (BDK / 651), 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone (I1173) and 2,4,6-trimethylbenzoyl diphenylphosphine oxide (TPO / 1110); The photoinitiator is preferably 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone (I2959); Preferably, the duration of the ultraviolet irradiation treatment in step (2) is selected from 20-60 min; More preferably, the duration of the ultraviolet irradiation treatment is 30 minutes; The purification process described in step (2) includes, but is not limited to, washing and drying processes; Furthermore, the solvent for washing is preferably at least one selected from acetone, dichloromethane, water, tetrahydrofuran, ethanol, and methanol; The washing solvent is preferably a combination of water and methanol, used for washing in sequence; The washing solvent is more preferably a combination of deionized distilled water and methanol, used for washing in sequence; Furthermore, the drying method includes, but is not limited to, at least one of vacuum drying, freeze drying, hot air circulation drying, combined vacuum and freeze drying, and supercritical drying; The preferred drying method is vacuum drying; The drying method is further preferably: vacuum drying at a temperature of 60 °C for 6-24 h. The drying method is more preferably vacuum drying at a temperature of 60 °C for 12 h.

[0032] Based on further solutions to the technical problems of the present invention, or simultaneous solutions to multiple technical problems, the preferred solution in the technical solution provided in the first aspect of the present invention includes: The first preferred embodiment is that the ratio of the molar mass of TAPB to the sum of the molar masses of DVA and DMTA is preferably 2:3. This technical solution, while addressing the technical problem of "improving synthesis yield and fluorescence stability," further addresses the technical problem of "further improving synthesis yield and fluorescence stability."

[0033] The second preferred embodiment: the irradiation intensity of the ultrasonic irradiation treatment is selected from 100-1000 W; preferably 560-1000 W; and more preferably 840 W. This technical solution, based on solving the technical problem of "improving synthesis yield and fluorescence stability", further solves the technical problem of "further improving synthesis yield and fluorescence stability".

[0034] The third preferred embodiment: the duration of the ultrasonic irradiation treatment is 20-60 min; preferably 50 min. This technical solution, based on solving the technical problem of "improving synthesis yield and fluorescence stability", further solves the technical problem of "further improving synthesis yield and fluorescence stability".

[0035] The fourth preferred embodiment: the range of X is 0 < X ​​< 1; preferably, the range of X is 0.5 ≤ X < 1; more preferably, X is 0.66. This technical solution, based on solving the technical problem of "improving synthesis yield and fluorescence stability", further solves the technical problem of "further improving synthesis yield and fluorescence stability".

[0036] Fifth preferred embodiment: The thiol monomer is selected from at least one of Cys, mercaptopropionic acid, 1-mercapto-2-propanol, 1,2-ethylenedithiol, and trimethylolpropanetrios(3-mercaptopropionate); preferably at least one of Cys and mercaptopropionic acid; more preferably Cys; and more preferably, the concentration of the Cys aqueous solution is selected from 28-112 mg / mL. -1 More preferably, the concentration of the Cys aqueous solution is 56 mg / mL. -1 This technical solution, while addressing the technical issues of "improving synthesis yield and fluorescence stability," further solves the technical problem of "achieving functional modification to specifically generate fluorescence response to MGO."

[0037] Secondly, the present invention provides the application of the preparation method in MGO detection.

[0038] This includes technical features: applications in MGO detection.

[0039] Preferably, the MGO detection is a fluorescence response analysis of MGO; Preferably, the application is that the preparation method can be used to indicate the content of MGO in dairy products to indirectly assess the level of glycosylation; Preferably, the application is that the preparation method can be used for the identification of the quality of Mānuka honey.

[0040] In this invention, Examples 1-7 at least support the protection scope of "ultrasonic irradiation treatment" and "ultraviolet irradiation treatment".

[0041] "Ultrasonic irradiation treatment" is summarized by the aforementioned explanation and / or the corresponding technical features in Examples 1-7, such as "the irradiation intensity of the ultrasonic irradiation treatment is selected from 100-1000 W; the irradiation intensity of the ultrasonic irradiation treatment is preferably 560-1000 W; the irradiation intensity of the ultrasonic irradiation treatment is further preferably 840 W; wherein the duration of the ultrasonic irradiation treatment is 20-60 min; the duration of the ultrasonic irradiation treatment is preferably 50 min," and the common feature "a physical treatment method that uses ultrasonic waves of specific frequency and power to transmit acoustic energy to the target object through a medium (such as liquid, solid, or gas), inducing physicochemical changes such as mechanical vibration, cavitation effect, thermal effect, or chemical effect, thereby achieving technical objectives such as material modification, biological sample processing, and pollutant degradation." Therefore, those skilled in the art can reasonably presume that "ultrasonic irradiation treatment," its subordinate concepts, its essentially equivalent technical means, and technical means that can replace it within the scope of conventional technical means and common knowledge based on the existing technical level should all fall within the protection scope of "ultrasonic irradiation treatment."

[0042] "Ultraviolet irradiation treatment" is a term derived from the aforementioned explanation and / or the corresponding technical features in Examples 1-7, such as "the duration of the ultraviolet irradiation treatment is selected from 20-60 min; more preferably, the duration of the ultraviolet irradiation treatment is 30 min," and is summarized by the common feature "a physical treatment method that uses ultraviolet light energy within a specific wavelength range as a radiation source to act on a target object (such as materials, microorganisms, liquid samples, etc.), and induces changes in the physical, chemical, or biological properties of the target object through photochemical, photothermal, or ionization effects to achieve technical objectives such as disinfection, sterilization, material modification, and surface activation." Therefore, those skilled in the art can reasonably presume that "ultraviolet irradiation treatment," its subordinate concepts, its essentially equivalent technical means, and technical means that can replace it within the scope of conventional technical means and common knowledge based on the existing technical level should all fall within the protection scope of "ultraviolet irradiation treatment."

[0043] In this invention, embodiments 1-7 at least support the protection scope of "Application in MGO detection".

[0044] The term "application in MGO detection" is a generalization derived from the foregoing explanation and / or the corresponding technical features in Examples 1-7, such as "the MGO detection is the fluorescence response analysis of MGO" and "the application is that this preparation method can be used to indicate the MGO content in dairy products to indirectly assess the glycosylation level." Therefore, those skilled in the art can reasonably presume that "application in MGO detection," its subordinate concepts, its essentially equivalent technical means, and technical means that can replace it within the scope of conventional and common knowledge based on the existing level of technology should all fall within the protection scope of "application in MGO detection."

[0045] The beneficial effects of this invention are as follows: The present invention has at least the following beneficial effects: (1) By comparison, the cavitation effect method based on sonochemistry (50 min) is much shorter in time than the solvothermal method (4320 min), and the morphology is more uniform and the fluorescence intensity is also greatly improved, indicating that the cavitation effect is indeed beneficial to the preparation of COF and can be used to quickly prepare uniform materials. (2) The COF material with good crystallinity can be prepared by the cavitation effect of sonic chemistry used in this invention; (3) Based on the light-triggered "click response", functional modifications can be made quickly; (4) The synthesized COF material can adsorb MGO, and MGO will trigger / induce its fluorescence response; (5) Compared with the prior art, the present invention provides a technical solution with a different technical concept, and its technical effect is equivalent to or slightly improved with the prior art. The difference between the technical concept of the present invention and the prior art includes, but is not limited to, "a specific combination of TAPB and DVA, DMPA, under the action of sound waves and light waves, realizes a rapid and efficient process of synthesizing COF, and the morphology is more uniform".

[0046] Furthermore, based on the present invention: 1. Based on the comparison of Examples 1-7 and Comparative Examples 1-2, the present invention employs a combination of technical means such as "TAPB, DVA, DMPA, etc.", achieving a new technical effect: "realizing a rapid and efficient synthesis process of COF, with a more uniform morphology." The combined technical effect is superior to the sum of the effects of each individual technical means. Attached Figure Description

[0047] Figure 1 S-[C=C] prepared for different power and time conditions 0.00 The fluorescence intensity and yield of COF are shown in the figure, where A represents S-[C=C] prepared at different powers. 0.00Fluorescence intensity and yield of COF; B in the figure represents S-[C=C] prepared at different times. 0.00 Fluorescence intensity and yield of COF.

[0048] Figure 2 [C=C] synthesized by acoustic and solvothermal methods 0.00 XRD images, fluorescence emission spectra, and SEM images of COFs, where A in the figure represents [C=C] synthesized by the acoustic and solvothermal methods. 0.00 XRD images of COF; B in the figure represents [C=C] synthesized by acoustic and solvothermal methods. 0.00 Fluorescence emission spectrum of COF; C in the figure represents [C=C] synthesized by acoustic method. 0.00 SEM analysis of COF; D in the figure represents [C=C] synthesized by the solvothermal method. 0.00 SEM analysis of COF.

[0049] Figure 3 S-[C=C] X Fluorescence emission spectrum and fluorescence intensity diagram of COF, where A in the figure represents S-[C=C]. X The fluorescence emission spectrum of COF; B in the figure represents S-[C=C]. X Fluorescence intensity diagram of COF.

[0050] Figure 4 For Cys to S-[C=C] 0.66 The effect of Cys concentration on fluorescence intensity and fluorescence spectrum is shown in the figure, where A represents the effect of different Cys concentrations on S-[C=C]. 0.66 The effect of fluorescence intensity; Figure B shows the effect of different Cys concentrations on S-[C=C]. 0.66 The influence of fluorescence emission spectrum.

[0051] Figure 5 For S-[Cys] 0.66 Characterization diagrams of COF, where A is the XRD pattern, B is the N2 adsorption-desorption curve, C is the TGA curve, D is the SEM image, E is the magnified local surface image, and F is the FT-IR spectrum.

[0052] Figure 6 For S-[Cys] under different conditions 0.66 The linear relationship between COF and different concentrations of MGO and the fluorescence response spectra are shown in the figure, where A represents the S-[Cys] concentration at different times. 0.66 The response of COF to MGO (400 μM) changes; B in the figure represents S-[Cys]. 0.66 Fluorescence response spectra of COF to different concentrations of MGO (1-600 μM); C in the figure represents S-[Cys]. 0.66The fluorescence response of COF is linearly related to the concentration of MGO; D in the figure represents the fluorescence response of S-[C=C] at different time points. 0.66 The response of COF to MGO (400 μM) changes; E in the figure represents S-[C=C] 0.66 Fluorescence response spectra of COF to different concentrations of MGO (1-600 μM); F in the figure represents S-[C=C]. 0.66 The fluorescence response of COF showed a linear relationship with the concentration of MGO.

[0053] Figure 7 For S-[Cys] 0.66 The fluorescence response of COF is compared with the linear calibration curves of 3-DG, GO, and 2,3-BD concentrations, along with response efficiency and electrostatic potential distribution. In the figure, A represents S-[Cys]. 0.66 The fluorescence response of COF is compared with the linear calibration curve of 3-DG concentration; B in the figure represents S-[Cys]. 0.66 The linear calibration curve of COF fluorescence response versus GO concentration; C in the figure represents S-[Cys]. 0.66 The fluorescence response of COF is compared with the linear calibration curve of 2,3-BD concentration; D in the figure represents S-[Cys]. 0.66 The response efficiency of COF to 3-DG, GO, 2,3-BD and MGO; E in the figure is the electrostatic potential distribution of MGO, 3-DG, 2,3-BD and GO.

[0054] Figure 8 For S-[Cys] 0.66 A comparison of the adsorption capacity of COF for MGO and its adsorption effects on MGO, GO, and 3-DG is shown in the figure, where A represents S-[Cys]. 0.66 Adsorption capacity diagram of COF for MGO; B in the diagram represents S-[Cys]. 0.66 COF adsorption of MGO, GO and 3-DG.

[0055] Figure 9 To investigate the effects of fluorescence quenching and the abundant components in the system on S-[Cys] 0.66 The graph shows the effect of the tested metal ion and its mixture (M1) on the COF fluorescence signal. 0.66 The effect of COF fluorescence signal; B in the figure represents the effect of amino acids, sugars, and their mixtures (M3) on S-[Cys] fluorescence signal. 0.66 The influence of COF fluorescence signal. Detailed Implementation

[0056] The following non-limiting embodiments are intended to enable those skilled in the art to gain a more comprehensive understanding of the present invention, but do not limit the invention in any way. The following content is merely an exemplary description of the scope of protection claimed by the present invention, and those skilled in the art can make various changes and modifications to the present invention based on the disclosed content, and such changes should also fall within the scope of protection claimed by the present invention.

[0057] The present invention will be further described below by way of specific embodiments. Unless otherwise specified, all instruments, devices, equipment, reagents, products, etc., used in the embodiments of the present invention are obtained through conventional commercial means.

[0058] Specific raw material information is shown in Table 1: Table 1. Raw Material Information

[0059] Example 1S-[Cys] 0.66 Synthesis of COF TAPB (84.3 mg, 0.24 mmol), DVA (44.7 mg, 0.24 mmol), and DMTA (23.3 mg, 0.12 mmol) were placed in centrifuge tubes containing 6 mL of HAc (6 M) and treated with a multi-purpose ultrasonic extractor under ultrasonic irradiation (840 W) for 50 min. The solids were thoroughly washed with acetone, dichloromethane, and MeOH sequentially, and finally dried under vacuum overnight to obtain S-[C=C]. 0.66 COF.

[0060] Weigh out 20 mg of S-[C=C] 0.66 COF powder was dispersed in 6 mL MeOH, and 2 mL Cys aqueous solution (56 mg / mL) was added. -1 112 mg of photoinitiator I2959 was added, and the mixture was irradiated in a UV crosslinker for 30 min to trigger the "click" reaction of the thiol-double bond. After the reaction, the crude product was washed with DDW and MeOH to remove unreacted Cys and photoinitiator, and then vacuum dried to obtain the S-[C=C] linked Cys. 0.66 COF (S-[Cys] ]0.66 COF) powder.

[0061] Example 2 S-[Cys] 0.33 Synthesis of COF TAPB (84.3 mg, 0.24 mmol), DVA (22.4 mg, 0.12 mmol), and DMTA (46.6 mg, 0.24 mmol) were placed in centrifuge tubes containing 6 mL of HAc (6 M) and treated with a multi-purpose ultrasonic extractor under ultrasonic irradiation (840 W) for 50 min. The solids were thoroughly washed with acetone, dichloromethane, and MeOH sequentially, and finally dried under vacuum overnight to obtain S-[C=C]. 0.33 COF.

[0062] Weigh out 20 mg of S-[C=C] 0.33 COF powder was dispersed in 6 mL MeOH, and 2 mL Cys aqueous solution (56 mg / mL) was added. -1 112 mg of photoinitiator I2959 was added, and the mixture was irradiated in a UV crosslinker for 30 min to trigger the "click" reaction of the thiol-double bond. After the reaction, the crude product was washed with DDW and MeOH to remove unreacted Cys and photoinitiator, and then vacuum dried to obtain the S-[C=C] linked Cys. 0.33 COF (S-[Cys]) 0.33 COF) powder.

[0063] The obtained S-[Cys] 0.33 The fluorescence intensity of COF is shown in the figure. Figure 3 The yield is shown in Table 2.

[0064] Example 3 S-[Cys] 0.50 Synthesis of COF TAPB (84.3 mg, 0.24 mmol), DVA (33.5 mg, 0.18 mmol), and DMTA (35.0 mg, 0.18 mmol) were placed in centrifuge tubes containing 6 mL of HAc (6 M) and treated with a multi-purpose ultrasonic extractor under ultrasonic irradiation (840 W) for 50 min. The solids were thoroughly washed with acetone, dichloromethane, and MeOH sequentially, and finally dried under vacuum overnight to obtain S-[C=C]. 0.50 COF.

[0065] Weigh out 20 mg of S-[C=C] 0.50 COF powder was dispersed in 6 mL MeOH, and 2 mL Cys aqueous solution (56 mg / mL) was added. -1112 mg of photoinitiator I2959 was added, and the mixture was irradiated in a UV crosslinker for 30 min to trigger the "click" reaction of the thiol-double bond. After the reaction, the crude product was washed with DDW and MeOH to remove unreacted Cys and photoinitiator, and then vacuum dried to obtain the S-[C=C] linked Cys. 0.50 COF (S-[Cys]) 0.50 COF) powder.

[0066] The obtained S-[Cys] 0.50 The fluorescence intensity of COF is shown in the figure. Figure 3 The yield is shown in Table 2.

[0067] Example 4 The difference from Example 1 is that the ultrasonic irradiation intensity is changed to 100 W, but everything else is the same.

[0068] The fluorescence intensity of the obtained product is shown in the figure. Figure 1 The yield is shown in Table 2.

[0069] Example 5 The difference from Example 1 is that the ultrasonic irradiation intensity is changed to 1000 W, but everything else is the same.

[0070] The fluorescence intensity of the obtained product is shown in the figure. Figure 1 The yield is shown in Table 2.

[0071] Example 6 The difference from Example 1 is that the duration of ultrasonic irradiation was changed to 20 minutes, while the rest were the same.

[0072] The fluorescence intensity of the obtained product is shown in the figure. Figure 1 The yield is shown in Table 2.

[0073] Example 7 The difference from Example 1 is that the duration of ultrasonic irradiation was changed to 60 minutes, but everything else is the same.

[0074] The fluorescence intensity of the obtained product is shown in the figure. Figure 1 The yield is shown in Table 2.

[0075] Comparative Example 1 (TAPB and DVA) The difference from Example 1 is that “TAPB (84.3 mg, 0.24 mmol), DVA (44.7 mg, 0.24 mmol) and DMTA (23.3 mg, 0.12 mmol)” is replaced with “TAPB (84.3 mg, 0.24 mmol) and DVA (67.05 mg, 0.36 mmol)”, and all other things are the same.

[0076] Comparative Example 2 (TAPB and DMTA) The difference from Example 1 is that “TAPB (84.3 mg, 0.24 mmol), DVA (44.7 mg, 0.24 mmol) and DMTA (23.3 mg, 0.12 mmol)” is replaced with “TAPB (84.3 mg, 0.24 mmol) and DMTA (69.9 mg, 0.36 mmol)”, and all other things are the same.

[0077] Comparative Example 3 (Traditional Method) Unlike Example 1, a conventional solvothermal method was used to prepare a solvothermal COF with the same monomer composition and ratio. Specifically, monomers with the same composition and ratio as those used in the ultrasonic cavitation method were dispersed in a 20 mL mixed solution of 1,2-dichlorobenzene and n-butanol (volume ratio 1:1), and after adding 2 mL of Hac (6 M), the solution was transferred to a high-temperature reactor and reacted at 120 °C for 72 h to obtain the COF.

[0078] Detection Example 1 The yields of COF prepared in the examples and comparative examples and the total reaction time used are shown in the table below: Table 2. Experiment Duration and Yield Results

[0079] Detection Example 2 I. Based on S-[Cys] 0.66 Establishment of a fluorescence response system for COF 1. Using S-[Cys] 0.66 The fluorescence response of COF to MGO is a typical experiment to establish the relationship between the concentration of the target analyte and the response signal.

[0080] S-[Cys] 0.66 COF dispersion in DDW yields S-[Cys] 0.66 COF suspension, with a concentration of 4 mg / mL -1 Then, an equal volume of MGO standard working solution (2-1200 μM) was mixed with S-[Cys] 0.66 The COF suspension was mixed, causing the S-[Cys] content in the mixture to increase. 0.66 The final concentration of COF was 2 mg / mL. -1 The final concentration of MGO was 1-600 μM. After sufficient contact between the two solutions, the maximum fluorescence emission intensity of the mixed solution at the optimal excitation wavelength (490 nm) was measured and denoted as F. The fluorescence intensity measured by replacing the MGO standard working solution with an equal volume of DDW was denoted as F0. Stern-Volmer Equation I was fitted to establish the S-[Cys] equation. 0.66 The linear relationship between COF fluorescence response (F0 / F) and MGO concentration: (I); Among them, C w The target working solution concentration is represented by , and k is the slope of the fitted calibration curve.

[0081] In experiments with other materials, only S-[Cys] was replaced in a single step. 0.66 The COF material was replaced with other materials of equal concentration, and the response signal was measured and the optical performance was evaluated without changing other operating conditions. In experiments with other target materials, only the MGO working solution was replaced with another target material in a single run, without changing other operating conditions, and the response signal was measured and the optical performance was evaluated.

[0082] LOD is calculated based on formula (II): (II); In the formula, SD represents 4 mg / mL -1 The standard deviation of the measured values ​​after mixing COF material with an equal volume of blank working solution.

[0083] 2. Based on the structural characteristics of the responder, the large number of coexisting components in the real sample matrix, and the elements that may affect the fluorescence results in conventional measurements.

[0084] GO, 3-DG, and 2,3-BD were selected as structural analogs of MGO for selectivity experiments, and the testing procedure was the same as in 1. Amino acids including valine, Lys, His, Arg, threonine, Cys, methionine, phenylalanine, leucine, tryptophan, and serine (400 μM) and carbohydrates including lactose, glucose, and ribose (0.1 mg / mL) were selected. -1 ) and its mixed solution M1 (the final concentration of amino acids was maintained at 400 μM, and the final concentration of carbohydrates was maintained at 0.1 mg / mL) -1 ), and including K + Na + Zn 2+ Mn 2+ Ca 2 + Mg 2+ Further selection specificity assessments were conducted using the metal ions (1 mM) and the mixed metal ion solution M3 (with the final metal ion concentration maintained at 1 mM). Additionally, based on mixed solution M1, a mixed solution M2 containing MGO (with both amino acids and MGO final concentrations maintained at 400 μM) and a mixed solution M4 containing MGO (with the final metal ion concentration maintained at 1 mM and the final MGO concentration maintained at 400 μM) were prepared for interference resistance assessments, with the testing procedures identical to those in step 1.

[0085] A stable fluorescence signal is one of the fundamental indicators for ensuring accurate detection and analysis. Therefore, this study investigated the detection of S-[Cys] prepared under greenhouse conditions (30 days), after exposure to ultraviolet irradiation (60 min), and in different batches. 0.66 Fluorescence signal of COF. The final concentration of S-[Cys]0.66 COF analyzed was maintained at 2 mg / mL. -1 The test procedure is the same as in step 1.

[0086] 3. Adsorption capacity assessment Evaluation of S-[Cys] through adsorption experiments 0.66 The adsorption capacity of COF for MGO. Weigh 2 mg of S-[Cys] 0.66 COF was dispersed in 6 mL of MGO standard solutions of different concentrations and shaken at 150 rpm for 5 min on a shaker. After centrifugation, the MGO content was determined by HPLC. The adsorption capacity (Qm) was calculated using formula (III): (III); In the formula, S is where C0 and C t represents the initial and time t, respectively; 6 represents the solvent volume (mL); and 2 represents S-[Cys]... 0.66 Mass of COF (mg).

[0087] II. Construction of Chemical Model System This study used Lys-MGO and casein-lactose models as typical chemical model systems to simulate dairy systems and evaluate the inhibitory effects of AGEs (Advanced Glycation End Products) from specific sources and during dairy processing. The Lys-MGO and casein-lactose models were based on previous studies with some modifications. Specifically, the Lys-MGO model consisted of 60 mM Lys and 60 mM MGO dissolved in 0.1 M PBS buffer (pH = 6.8), and the casein-lactose model consisted of 3.0 g casein and 5.1 g lactose dissolved in 0.1 M PBS buffer (pH = 6.8). The simulation systems were treated at 65 °C for 30 min to simulate sterilization. After the reaction, the systems were rapidly cooled in ice water and stored at 4 °C. The Lys-MGO and casein-lactose models were named M1 and M2, respectively, for subsequent analysis. In evaluating the inhibitory effect, 6 mL of M1 and M2 were respectively added to 12 mg (0.2% w / v) S-[Cys]. 0.66 COF was then followed by a simulated sterilization process. After the reaction, S-[Cys] was separated by centrifugation. 0.66 COF was then analyzed, followed by determination of AGEs content and comparison with that without S-[Cys]. 0.66The amount of AGEs generated in the blank control group of the COF simulation system was compared. The inhibition rate was calculated using formula (Ⅳ): (Ⅳ).

[0088] 1. Analysis of actual samples Dairy products and honey were used as samples to verify the S-[Cys]-based assay. 0.66 Feasibility of COF in detecting MGO in food samples. Samples were diluted 5-fold and centrifuged (10000 rpm, 10 min). The supernatant was then mixed with an equal volume of S-[Cys]. 0.66 COF suspension (2 mg mL) -1 Mix the ingredients, incubate for 5 minutes, and then perform fluorescence analysis.

[0089] 2. Analysis of α-dicarbonyl compounds and AGEs using large-scale instruments (1) Analysis of α-dicarbonyl compounds: Using o-PD as a derivatizing agent, 1 mL of sample was reacted with 0.5 mL of o-PD (100 mM) and 0.5 mL of 2,3-dimethylquinoxaline internal standard at room temperature in the dark for 30 min. The sample was then filtered through a 0.22 μM filter before HPLC analysis. The HPLC conditions were as follows: column: Inertsil ODS-SP (4.6 mm × 250 mm, 5 μm); mobile phase A: 1% trifluoroacetic acid ultrapure water; mobile phase B: MeOH, A:B = 1:1; flow rate: 1 mL min⁻¹; injection volume: 5 μL; temperature: 25 ℃; wavelength: 315 nm.

[0090] (2) Analysis of AGEs: 1 mL of sample was vortexed with 5 mL of 1% trichloroacetic acid solution for 30 s, followed by 5 mL of ACN and vortex dispersion. The mixture was then subjected to ultrasonic-assisted extraction (10 min) and centrifuged (10000 rpm, 10 min), collecting the supernatant. 10 mL of n-hexane was added to the solution for liquid-liquid extraction to remove lipid interference. After centrifugation (10000 rpm, 10 min), the n-hexane was removed, and the solution was concentrated to 5 mL by nitrogen blowing. The solution was then purified using an HLB SPE column. After purification, the sample was reconstituted with 0.1% formic acid aqueous solution, vortexed for 1 min, and filtered through a 0.22 μM filter membrane for HPLC-MS / MS analysis. The HPLC-MS / MS conditions were as follows: Column: Acquity UPLC BEHC18 (2.1 mm × 100 mm, 1.7 μm); Mobile phase A: 0.1% formic acid aqueous solution; Mobile phase B: water; Elution program: 0–5 min, 70% B; 5–7 min, 50%–70% B; 5–7 min, 70%–20% B; 7–8 min, 20% B; 8–8.5 min, 20%–70% B; 8.5–10 min, 70% B; Flow rate: 0.3 mL min⁻¹; Injection volume: 5 μL; Temperature: 30 °C; Ion mode: ESI+ mode; Monitoring mode: MRM; Specific parameters: CML: m / z 205.2→84.1, CEL: m / z 219.2→83.9, PYR: m / z 255.2→175.0.

[0091] Table 3. S-[Cys] 0.66 COF for the detection of MGO in real samples

[0092] Verification of technical effectiveness and / or analysis of technical problem solving 1. The transient energy provided by cavitation can serve as a powerful synthesis tool, exhibiting unique advantages in improving synthesis efficiency. Numerous studies have shown a nonlinear correlation between the adjustment of relevant parameters and the performance of the applied system.

[0093] Therefore, the impact of relevant parameters on the application system is first explored. Taking S-[C=C] as an example... 0.00 COF is a typical structure; the effect of acoustic irradiation energy on S-[C=C] is investigated. 0.00 The effect of COF material fluorescence intensity and yield. Results are as follows: Figure 1 As shown in Figure A, with the increase of sound wave irradiance, S-[C=C] 0.00 The fluorescence intensity of the COF material gradually increases. Significance analysis revealed that when the intensity exceeds 840 W, S-[C=C]... 0.00The fluorescence intensity of COF no longer showed a significant increase. Meanwhile, S-[C=C]... 0.00 The synthesis yield of COF materials increased with increasing strength, rising from 14.5% to 81.2%, a 5.6-fold increase. These results indicate that high-intensity acoustic-induced high-speed jets and shock waves can significantly contribute to improved synthesis yield and enhanced performance.

[0094] 2. Investigating the effect of irradiation time on S-[C=C] 0.00 The influence of COF material properties.

[0095] The results are as follows Figure 1 As shown in Figure B, the yield significantly increases with increasing irradiation time, but stops increasing after 50 min. This is likely because the solvent in the sample system has almost completely evaporated after 50 min of acoustic irradiation. The lack of a reaction medium makes it difficult to achieve efficient building blocks even under cavitation effects. In contrast, time has a smaller effect on fluorescence intensity, possibly because the washing operation after the reaction removes unreacted units, leaving the successfully synthesized S-[C=C] structure. 0.00 COF results in relatively small changes in fluorescence intensity, which also indicates that S-[C=C] synthesized via acoustic irradiation... 0.00 The fluorescence performance of COF is relatively stable.

[0096] 3. The cavitation effect of sonicochemistry can accelerate the rate and efficiency of reactions.

[0097] First, XRD confirmed that both formed crystal structures. Figure 4 In A), and S-[C=C] 0.00 The lattice planes of COF are more clearly defined. This was subsequently confirmed by fluorescence measurement. Figure 4 In section B), it was found that S-[C=C] prepared by ultrasonic cavitation... 0.00 The fluorescence intensity of COF synthesized by ultrasonic cavitation was 41 times that of COF synthesized by solvothermal method. Furthermore, comparing their surface morphologies, it was observed that the material prepared by ultrasonic cavitation was more regular and uniform, while the material prepared by solvothermal method was more aggregated. In summary, the ultrasonic cavitation method (50 min) is significantly shorter than the solvothermal method (4320 min), and produces a more uniform morphology with a substantial increase in fluorescence intensity, indicating that the cavitation effect is indeed beneficial for COF preparation and can be used to rapidly achieve the preparation of uniform materials.

[0098] 4. S-[C=C] 0.00The side chains of the building units in the COF structure are methoxy groups. The lone pair of electrons on the methoxy group can conjugate with the benzene ring in the structure, enhancing the stability of the COF structure. When the methoxy-containing monomer is replaced with a vinyl-containing monomer, the C=C of the side chain can provide an activation site for the photoinduced "click reaction," thereby allowing the thiol group of Cys to be stably linked to the vinyl group.

[0099] Therefore, DVA containing vinyl side chains was subsequently used to replace DMTA containing methoxy side bonds, and S-[C=C] was named according to the proportion of DVA. X COF (X = 0.00, 0.33, 0.50, 0.66, and 1.00). S-[C=C] was synthesized under the acoustic irradiation parameters investigated above. X COF, its fluorescence characteristics are as follows Figure 2 As shown: With the increase of the proportion of DVA containing vinyl side chains, S-[C=C] X The fluorescence intensity of COF decreases accordingly; when DVA completely replaces DMTA, the fluorescence intensity is almost negligible.

[0100] 5. Under the induction of ultraviolet light irradiation, a thiol "click reaction" occurs, thereby stably linking Cys to COF and exposing the amino group of Cys to S-[C=C]. 0.66 Within the pore size of COF. Therefore, the amount of Cys containing thiol groups was optimized. Observations revealed ( Figure 4 In part A), when the concentration is greater than 56 mg / mL -1 At that time, it is possible that the reaction sites are already saturated, S-[C=C] 0.66 The fluorescence intensity of COF no longer changes, thus allowing selection of 56 mg / mL. -1 For the subsequent S-[Cys] 0.66 The amount of COF used is determined to prepare S-[Cys]. 0.66 .

[0101] Furthermore, by comparing the fluorescence emission of its response, it was found that when Cys is grafted onto S-[C=C]... 0.66 After COF, the optimal emission wavelength is determined by S - [C = C]. 0.66 COF exhibits a 50 nm redshift at 510 nm, S-[Cys] 0.66 The optimal emission wavelength for COF is 560 nm. This is due to the thiol group of Cys reacting with S-[C=C]. 0.66 The vinyl bonding reaction of COF affects the electron distribution of the entire skeleton, causing intramolecular charge transfer and energy dissipation, which manifests as a redshift in wavelength and a decrease in intensity.

[0102] 6. The crystal structure of S-[Cys]0.66COF was determined, and the structure of S-[Cys]0.66COF was simulated and analyzed using Materials Studio. The results are as follows: Figure 5 As shown, the sharp diffraction peaks in the experimental results prove that S-[Cys] 0.66 COF exhibits good crystallinity. It can be observed that the light-triggered "click reaction" not only has a short reaction time but also effectively preserves S-[Cys] 0.66 The crystal structure of COF is shown. Its strong diffraction peaks at 2.79°, 4.85°, 5.57°, and 7.36°, and its weak diffraction peak at 25.13°, correspond to the (100), (110), (200), (120), and (001) crystal planes, respectively, indicating that S-[Cys] 0.66 COF has a high degree of crystallinity.

[0103] By comparing the experimental data with the simulation results of AA stacking and AB stacking, it can be observed that the diffraction angle of the simulated AA stacking is in high agreement with the experimental results. From this, it can be inferred that S-[Cys] 0.66 The packing pattern of COF is AA packing. Specific surface area and pore size distribution are closely related to the adsorption level. Therefore, N2 adsorption-desorption experiments were used to study the specific surface area and pore size distribution. The results are as follows: Figure 5 As shown in Figure B, S-[Cys] is calculated based on BET. 0.66 The specific surface area of ​​COF is 63.98 m². 2 g -1 The pore size distribution, calculated using NLDFT, is predominantly 2.0 nm.

[0104] Thermogravimetric analysis of S-[C=C] 0.66 Thermal stability of COF. For example... Figure 5 As shown in Figure C, the curve exhibits only one inflection point for mass loss. When the temperature reaches 429 ℃, S - [C = C] 0.66 The mass of COF decreases significantly, likely due to structural collapse and decomposition. However, the mass loss is less than 10% at this temperature and less than 5% at 300 °C, indicating that S-[Cys]... 0.66 COF exhibits good thermal stability, which is sufficient to meet the temperature requirements of the current research.

[0105] The morphology of a material affects its interaction efficiency with guest molecules; therefore, SEM is used to study S-[Cys]... 0.66 The morphology of COF was characterized. For example... Figure 5 As shown in D, S-[Cys] 0.66 The morphology of COF and S-[C=C] 0.66COF did not show significant differences, exhibiting a relatively uniform fibrous structure, and Figure 2 By comparing the morphology shown in C, it can be inferred that the light-triggered "click response" does not significantly affect the surface of the material structure. Further magnification of the surface reveals (...). Figure 5 The surface of E in Cys is relatively rough, exposing more interaction sites, which is beneficial for interaction with guest molecules. Furthermore, the EDS elemental analysis in the inset shows a uniform distribution of C, O, N, and S elements. The uniform distribution of S, unique to Cys, also verifies that Cys is extensively linked within the backbone structure.

[0106] Subsequently, the S-[Cys] were analyzed via FT-IR. 0.66 The structural characteristics of COF were investigated. For example... Figure 5 The FT-IR spectrum of F in the TAPB monomer is shown, located at 3358 cm⁻¹. -1 The characteristic absorption peaks are due to the stretching vibration of -NH2, DVA, DMTA, and S-[C=C]. 0.66 COF is located at 1692 cm -1 The absorption peak at that point is attributed to the presence of the carbonyl group. It is worth noting that S-[C=C]... 0.66 COF 1610 cm -1 The newly appearing absorption peak is attributed to the stretching vibration of C=N generated by the Schiff base reaction, confirming the successful synthesis of S-[C=C] via condensation reaction. 0.66 COF, 676 cm -1 The absorption peak at 675 cm⁻¹ originates from CS generated by the "click reaction," indicating that the functional monomer was successfully grafted into the pore interior through Cys covalent modification. The corresponding Gua COF peak at 675 cm⁻¹... -1 The CS characteristic peak at the aperture originates from the light-triggered "click reaction," indicating that the functional monomer was successfully grafted into the aperture through covalent modification.

[0107] 7. Research on S-[Cys] 0.66 The fluorescence response of COF to MGO. For example... Figure 6 As shown in A, within the first 5 minutes, with S-[Cys]... 0.66 As the contact time between COF and MGO (400 μM) increases, the fluorescence response value also rises, subsequently entering a relatively stable plateau phase, indicating that S-[Cys] 0.66 The response of COF to MGO is fully completed within 5 minutes, providing a stable fluorescence signal. S-[Cys] 0.66 COF adsorption of MGO is based on the high affinity of MGO for amino groups, which binds MGO to S-[Cys] via hydrogen bonding. 0.66In COF. Towards S-[Cys] 0.66 COF was supplemented with different concentrations of MgO and S-[Cys]. 0.66 COF showed a clear fluorescence response signal, namely S-[Cys]. 0.66 The fluorescence intensity of COF decreased with increasing MGO concentration. The relationship between the fluorescence response signal and the MGO concentration was established by fitting an equation, and the results are as follows: Figure 6 As shown in C, the fitting equation is expressed as F0 / F=0.0015C. w +0.9646, the two show a good linear relationship (R0). 2 =0.9934), with a LOD of 0.87 μM. For comparison, the original S-[C=C] was also investigated. 0.66 The fluorescence response of COF to MGO. For example... Figure 6 As shown in D, S-[C=C] 0.66 The COF reached equilibrium with MGO within 3 minutes, exhibiting a faster mass transfer rate. However, for the same concentration of MGO (400 μM), S-[C=C] 0.66 The COF response value is 1.28, which is lower than that of S-[Cys]. 0.66 The COF response value (1.59) indicates that Cys grafting may have enhanced its recognition feedback effect on MGO. Subsequently, different concentrations of MGO solutions and S-[C=C] were selected. 0.66 The fluorescence response after sufficient contact with COF was verified. For example... Figure 6 As shown in E, the increase in MGO concentration affects S-[C=C]. 0.66 The decrease in COF fluorescence has a relatively small impact, as shown by the fitted curve (F0 / F=0.0007C). w +0.9843, R 2 =1.0268) can further confirm that grafting Cys into the framework material is beneficial for the capture and identification of MGO.

[0108] S-[Cys] was then evaluated. 0.66 COF adsorption capacity for MGO. For example... Figure 8 As shown in Figure A, with increasing MGO concentration, S-[Cys] 0.66 The amount of MGO adsorbed by COF also increases accordingly. When the MGO concentration is higher than 172.8 mg / mL... -1 At that time, S-[Cys] 0.66 The adsorption capacity of COF for MGO reaches a plateau and no longer increases significantly, thus yielding S-[Cys] 0.66 The maximum adsorption capacity of COF for MGO is 91.0 mg g. -1This is sufficient to meet the needs of the application. Furthermore, the adsorption capacities of two other key AGE intermediates, GO and 3-DG, were compared ( Figure 8 (As shown in B in the figure). Although the adsorption capacity for 3-DG is higher, further calculations and comparisons were performed considering the molecular weight of the structure. Using MGO as a reference, the relative adsorption capacities of GO and 3-DG are 38.5% and 47.6% of those of MGO, respectively, which also indirectly demonstrates the adsorption effect on the α-dicarbonyl structure and its potential to inhibit the formation of AGEs converted from it.

[0109] 8. Three structural analogues of MGO, GO, 2,3-BD, and 3-DG (1-600 μM), were selected to target S-[Cys]. 0.66 The selectivity of COF was evaluated. Figure 7 The existence of 3-DG and GO can be seen in AC, which affects S-[Cys]. 0.66 COF had almost no effect, and 2,3-BD showed a weak response, but even at a high concentration of 600 μM, its effect was very limited. Further comparison was made of the slope of the linear relationship between the response signal and the concentration. Figure 7 As can be seen in D, S-[Cys] 0.66 The response efficiency of COF to MGO is significantly higher than that of 3-DG, GO, and 2,3-BD, being 15, 15, and 3.75 times higher, respectively. This difference in response may be related to charge distribution. Figure 7 As shown in Figure E, the higher electrostatic potential of MGO (red area) is more concentrated, making it more susceptible to attraction with the amino groups in the COF structure. In summary, the experimental results indicate that the IFE mechanism can promote the attraction of S-[Cys]... 0.66 COF generates a response signal to MGO, which can be used to indicate MGO molecules in the system.

[0110] Subsequently, the effects of components that may cause fluorescence quenching and are abundant in the system on S-[Cys] were investigated. 0.66 The influence of COF fluorescence signal was investigated. For example... Figure 9 As shown in A, the tested metal ions and their mixture (M1) have virtually no effect on S-[Cys]. 0.66 The fluorescence of COF was observed, and MGO molecules in multi-component systems could be precisely captured and a feedback signal generated in M2 solutions containing MGO. Similarly, amino acids, sugars, and their mixtures (M3) showed positive effects on S-[Cys]... 0.66 The influence of COF fluorescence signal is also negligible. Figure 9 B in the MGO solution showed a significant fluorescence response in M4 solution containing MGO.

[0111] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A method for preparing fluorescent COF based on acoustic and optical wave assistance, characterized in that, Including the following steps: (1) TAPB, DVA, DMTA and the catalyst were dissolved in water and mixed, then purified by ultrasonic irradiation to obtain the S-[C=C] mixture. X COF, where X is the percentage of the mass of DVA in the sum of the masses of DVA and DMTA; X is selected from 0 < X ​​< 1; (2) Take the S-[C=C] obtained in step (1) X COF is dissolved in a solvent and mixed with a thiol monomer and a photoinitiator. After being treated with ultraviolet irradiation, the mixture is purified to obtain the fluorescent COF.

2. The preparation method according to claim 1, characterized in that, The ratio of the molar mass of TAPB to the sum of the molar masses of DVA and DMTA in step (1) is 2:

3.

3. The preparation method according to claim 1, characterized in that, The catalyst in step (1) is selected from at least one of formic acid, acetic acid, trifluoroacetic acid and p-toluenesulfonic acid; Acetic acid is preferred.

4. The preparation method according to claim 1, characterized in that, The irradiation intensity of the ultrasonic irradiation treatment in step (1) is selected from 100-1000W; preferably 560-1000W; more preferably 840W; The duration of the ultrasonic irradiation treatment in step (1) is 20-60 min; preferably 50 min.

5. The preparation method according to claim 1, characterized in that, The range of X in step (1) is 0.5 ≤ X < 1; preferably 0.

66.

6. The preparation method according to claim 1, characterized in that, The purification process in step (1) includes washing and drying. Further, the washing solvent is at least one selected from acetone, dichloromethane, water, tetrahydrofuran, ethanol, and methanol; preferably, acetone, dichloromethane, and methanol are used in combination for sequential washing. Furthermore, the drying method is selected from at least one of vacuum drying, freeze drying, hot air circulation drying, vacuum freeze-drying combined with supercritical drying; preferably, vacuum drying; more preferably, vacuum drying is carried out at a temperature of 30-80°C for 6-24 hours; even more preferably, vacuum drying is carried out at a temperature of 60°C for 12 hours.

7. The preparation method according to claim 1, characterized in that, The solvent in step (2) is selected from at least one of methanol, ethanol, N,N-dimethylformamide, acetone and isopropanol; Methanol is preferred; The thiol monomer in step (2) is selected from at least one of Cys, mercaptopropionic acid, 1-mercapto-2-propanol, 1,2-ethylenedithiol and trimethylolpropane tris(3-mercaptopropionate); Preferably, it is at least one of Cys and mercaptopropionic acid; Cys is further preferred; A further preferred option is an aqueous Cys solution; The optimal concentration is 28-112 mg / mL. -1 Cys aqueous solution; The photoinitiator in step (2) is selected from at least one of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone, 1-hydroxycyclohexylphenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone and 2,4,6-trimethylbenzoyl diphenylphosphine oxide; The preferred option is 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone.

8. The preparation method according to claim 1, characterized in that, The duration of the ultraviolet irradiation treatment in step (2) is selected from 20-60 min; preferably 30 min.

9. The preparation method according to claim 1, characterized in that, The purification process in step (2) includes washing and drying. Further, the washing solvent is at least one selected from acetone, dichloromethane, water, tetrahydrofuran, ethanol, and methanol; preferably, water and methanol are used in combination for washing in sequence; more preferably, deionized distilled water and methanol are used in combination for washing in sequence. Furthermore, the drying method is selected from at least one of vacuum drying, freeze drying, hot air circulation drying, vacuum freeze-drying combined with supercritical drying; preferably, vacuum drying; more preferably, vacuum drying is carried out at a temperature of 60 °C for 6-24 h; even more preferably, vacuum drying is carried out at a temperature of 60 °C for 12 h.

10. The application of the preparation method according to any one of claims 1-9 in the detection of MGO.

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