A one-step method for the preparation of fluorescent single-stranded polymer nanoparticles

Abstract

The application discloses a one-step preparation method of fluorescent single-chain polymer nanoparticles, and particularly relates to the field of high polymer chemistry. The method comprises the following steps: dissolving polyethylene glycol methyl ether methacrylate, cyanostilbene methacrylate monomer and an initiator in a ninth solvent to obtain a reaction solution; performing a polymerization reaction on the reaction solution under a nitrogen environment to obtain poly((Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tri(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)methyl acrylate-polyethylene glycol methyl ether methacrylate); dissolving the product in water to obtain a copolymer solution; irradiating the copolymer solution under a UV lamp; and performing freeze-drying separation to obtain fluorescent single-chain polymer nanoparticles. The one-step preparation of the fluorescent polymer single-chain nanoparticles is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of preparation methods of fluorescent single-chain polymers, in particular to a one-step method for preparing fluorescent single-chain polymer nanoparticles. BACKGROUND

[0002] Single-chain polymer nanoparticles are a kind of small-sized (20 nm or less) materials prepared by intramolecular cross-linking of polymer chains. Their formation process can mimic the folding and molecular transport functions of proteins, and thus has become a research hotspot in the fields of chemistry, materials science and life science. Among them, fluorescent single-chain polymer nanoparticles have attracted extensive research enthusiasm due to their excellent biocompatibility and fluorescence function, and have been applied in the fields of catalysis, biosensors, nano-reactors, nano-drugs, etc.

[0003] Document 1 “J. F. Hoffmann, A. H. Roos, F.-J. Schmitt, D. Hinderberger, and W. H. Binder. Fluorescent and Water Dispersible Single-Chain Nanoparticles: Core-Shell Structured Compartmentation. Angew. Chem. Int. Ed. 2021, 60, 7820-7827” discloses a kind of single-chain polymer nanoparticles which are first prepared by click reaction between azide and alkyne as intramolecular folding mechanism, and then the formed single-chain polymer nanoparticles are labeled with fluorescent dyes to obtain fluorescent single-chain polymer nanoparticles. The preparation method of this fluorescent single-chain polymer nanoparticles needs more than two steps of chemical reaction, the formed single-chain polymer nanoparticles need additional reactive functional groups to introduce fluorescent units, and the introduction of fluorescent units has many structural uncertainties, which is difficult to realize one-step simple preparation.

[0004] Reference 2, “Y. Shao, Y.-L. Wang, Z. Tang, Z. Wen, C. Chang, C. Wang, D.Sun, Y. Ye, D. Qiu, Y. Ke, F. Liu, and Z. Yang. Scalable Synthesis of Photoluminescent Single-Chain Nanoparticles by Electrostatic-Mediated Intramolecular Crosslinking. Angew. Chem. Int. Ed. 2022, 61, e202205183,” discloses a method for preparing fluorescent single-chain polymer nanoparticles by first modifying a polymer with fluorescent moieties, and then adding a photocrosslinking agent to initiate intra-chain crosslinking. This method requires more than two chemical reaction steps, and the introduced fluorescent moieties can affect the intra-chain folding and crosslinking of the polymer. Summary of the Invention

[0005] The main objective of this application is to provide a one-step method for preparing fluorescent single-chain polymer nanoparticles, aiming to achieve a simple one-step preparation of fluorescent single-chain polymer nanoparticles.

[0006] To achieve the above objectives, this application provides a fluorescent single-chain polymer nanoparticle with the following structural formula:

[0007] .

[0008] Optionally, x+y=1 in the structural formula.

[0009] To achieve the above objectives, this application also provides a one-step method for preparing fluorescent single-chain polymer nanoparticles, comprising:

[0010] Polyethylene glycol methyl ether methacrylate, cyanostilbene methacrylate monomers and initiator were dissolved in a ninth solvent to obtain a reaction solution. The reaction solution was subjected to a polymerization reaction under nitrogen atmosphere to obtain poly((Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate-polyethylene glycol methyl ether methacrylate);

[0011] Poly((Z)-2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate-polyethylene glycol methyl ether methacrylate) was dissolved in water to obtain a copolymer solution. The copolymer solution was irradiated under a UV lamp and then lyophilized to obtain fluorescent single-chain polymer nanoparticles.

[0012] Optionally, a method for preparing cyanostilbene methacrylate monomer includes:

[0013] 3,4,5-trihydroxybenzaldehyde, 1-bromododecane, tetrabutylammonium iodide and potassium carbonate were dissolved in a first solvent and subjected to a first substitution reaction to obtain 3,4,5-tris(dodecyloxy)benzaldehyde.

[0014] 3,4,5-tris(dodecyloxy)benzaldehyde was dissolved in a second solvent to obtain a 3,4,5-tris(dodecyloxy)benzaldehyde solution. Lithium aluminum hydride solution was added dropwise to the 3,4,5-tris(dodecyloxy)benzaldehyde solution and a reduction reaction was carried out to obtain 3,4,5-tris(dodecyloxy)benzyl alcohol.

[0015] 3,4,5-tris(dodecyloxy)benzyl alcohol was dissolved in a third solvent to obtain a 3,4,5-tris(dodecyloxy)benzyl alcohol solution. Phosphorus tribromide solution was added dropwise to the 3,4,5-tris(dodecyloxy)benzyl alcohol solution, and a second substitution reaction was carried out to obtain 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene.

[0016] 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene, trimethylcyanosilane and tetrabutylammonium fluoride are dissolved in a fourth solvent and undergo a first nucleophilic substitution reaction to give 3,4,5-tris(dodecyloxy)phenylacetonitrile;

[0017] Triethylene glycol and triethylamine were dissolved in a fifth solvent to obtain a first mixed solution. A 4-toluenesulfonyl chloride solution was added dropwise to the first mixed solution, and a second nucleophilic substitution reaction was carried out to obtain p-toluenesulfonate-tetraethylene glycol.

[0018] p-Toluenesulfonate-tetraethylene glycol, p-hydroxybenzaldehyde, and carbonic acid were dissolved in a sixth solvent and subjected to a first nucleophilic addition reaction to yield 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde;

[0019] 3,4,5-tris(dodecyloxy)phenylacetonitrile and 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde were dissolved in a seventh solvent and subjected to a second nucleophilic addition reaction and a dehydration reaction to obtain (Z)-3-(4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)phenyl)-2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile;

[0020] (Z)-3-(4-(2-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)phenyl)-2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile and triethylamine were dissolved in an eighth solvent to obtain a second mixed solution. A methacryloyl chloride solution was added dropwise to the second mixed solution, and a third nucleophilic substitution reaction was carried out to obtain the cyanostilbene methacrylate monomer.

[0021] Optionally, in the first substitution reaction, the molar ratio of 3,4,5-trihydroxybenzaldehyde, 1-bromododecane, tetrabutylammonium iodide, and potassium carbonate is 1:3:0.1:(3~1):5:0.2:8, the reaction temperature is 80~85℃, and the reaction time is 12-24h; in the reduction reaction, the molar ratio of 3,4,5-tris(dodecyloxy)benzaldehyde to lithium aluminum hydride in the lithium aluminum hydride solution is 1:1~2, the dropping temperature is -5~5℃, and the reaction conditions are: reacting at -5~5℃ for 0.5~1h, followed by reacting at 20~30℃ for 2~3h; in the second substitution reaction, 3,4, The molar ratio of 5-tris(dodecyloxy)benzyl alcohol to phosphorus tribromide in the solution is 1:1~2, the dropping temperature is -5~5℃, the reaction temperature is 20~30℃, and the reaction time is 3~4h; in the first nucleophilic substitution reaction, the molar ratio of 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene, trimethylcyanosilane, and tetrabutylammonium fluoride is 1:1.2:0.2~1:1.5:1.5, the reaction temperature is 20~30℃, and the reaction time is 3~4h.

[0022] Optionally, in the second nucleophilic substitution reaction, the molar ratio of 4-toluenesulfonyl chloride, tetraethylene glycol, and triethylamine in the reaction solution is 1:1:(1.1~4):1:1.2, the dropping temperature is -5~5℃, the reaction temperature is 20~30℃, and the reaction time is 0.5~1h; in the first nucleophilic addition reaction, the molar ratio of p-toluenesulfonate-tetraethylene glycol, p-hydroxybenzaldehyde, and carbonic acid is 1:1:(2~1.1):1:3, the reaction temperature is 80~85℃, and the reaction time is 12~24h; in the second nucleophilic addition reaction, the molar ratio of 3,4,5-tris(dodecyloxy)phenylacetonitrile and 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde is 1~1.2:1, the reaction temperature is 40~50℃, and the reaction time is 12~24h;

[0023] In the third nucleophilic substitution reaction, the molar ratio of (Z)-3-(4-(2-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)phenyl)-2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile, triethylamine, and methacryloyl chloride solution in the methacryloyl chloride solution is 1:1:(1.5~1):3:3, the dropping temperature is -5~5℃, the reaction temperature is 20~30℃, and the reaction time is 12~24h.

[0024] Optionally, the first solvent is an N,N-dimethylformamide solution, the second solvent is a tetrahydrofuran solution, the third solvent is a dichloromethane solution, the fourth solvent is acetonitrile; the fifth solvent is a dichloromethane solution, the sixth solvent is an N,N-dimethylformamide solution, the seventh solvent is a mixed solution of ethanol and tetrabutylammonium hydroxide with a volume ratio of ethanol to tetrabutylammonium hydroxide of 20~30:1, and the eighth solvent is a dichloromethane solution.

[0025] Optionally, the reaction solution is subjected to a freeze-vacuum-thaw cycle in a nitrogen atmosphere before the polymerization reaction; and the reaction products are separated and purified after the polymerization reaction.

[0026] Optionally, the polymerization reaction temperature is 73~76℃, the reaction time is 10~12h with stirring; the ninth solvent is tetrahydrofuran solution; the wavelength of the ultraviolet lamp is 365 nm, and the irradiation time is 6~12h.

[0027] To achieve the above objectives, this application also provides the application of fluorescent single-chain polymer nanoparticles in catalysts, biosensors, nanoreactors, or nanomedicines.

[0028] Compared with the prior art, the beneficial effects of this application are as follows:

[0029] This invention proposes a one-step method for preparing fluorescent single-chain polymer nanoparticles. First, hydrophobic cyanobrythril methacrylate monomer ((Z)-2-(2-(2-(2-(4-(2-cyano-2-)) is used. (3,4,5-Tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate) was copolymerized with hydrophilic polyethylene glycol monomethyl ether methacrylate monomer to obtain a random copolymer. In the single-chain aggregated state of this random copolymer, the hydrophobic cyanostylene moiety can simultaneously have both ordered stacking and monomolecular dispersion states. The ordered stacked cyanostylene moiety undergoes intermolecular [2+2] cycloaddition under light irradiation, achieving intra-chain crosslinking of the polymer chain without the need for additional crosslinking agents. The dispersed cyanostylene moiety undergoes intramolecular cyclization under light irradiation to produce phenanthrene derivatives with strong fluorescence properties, achieving strong fluorescence properties without the need for post-modification of fluorescent moiety moiety. Therefore, a "one-step" preparation method for fluorescent polymer single-chain nanoparticles has been achieved. At the same time, this "one-step" preparation method for fluorescent polymer single-chain nanoparticles can simulate the changes in structure and function during protein folding. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the molecular folding of a single-chain polymer prepared by a one-step method for preparing fluorescent single-chain polymer nanoparticles according to this application.

[0031] Figure 2 An atomic force microscope image of a single-chain polymer prepared by a one-step method for preparing fluorescent single-chain polymer nanoparticles according to this application;

[0032] Figure 3 This is a comparison of gel permeation chromatography before and after light irradiation of the single-chain polymer prepared by the "one-step" preparation method of fluorescent single-chain polymer nanoparticles according to this application.

[0033] Figure 4 This is a schematic diagram showing the fluorescence spectrum change of a single-chain polymer prepared by the "one-step" preparation method of fluorescent single-chain polymer nanoparticles according to this application under ultraviolet light irradiation.

[0034] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] The first embodiment of the present invention provides fluorescent single-chain polymer nanoparticles, which are viscous yellow solids with the following structural formula:

[0037]

[0038] Where x + y = 1.

[0039] The second embodiment of the present invention provides a one-step preparation method for fluorescent single-chain polymer nanoparticles, the preparation method comprising:

[0040] Step S1: Polyethylene glycol methyl ether methacrylate, cyanostilbene methacrylate monomers, and initiator are dissolved in the ninth solvent to obtain a reaction solution. The reaction solution is placed in a dry Schlenk tube under a nitrogen atmosphere and subjected to multiple freeze-vacuum-thaw cycles. Subsequently, the polymerization reaction is carried out by stirring at 73~76℃ for 10~12h. After the reaction is completed, the product is purified by column chromatography to obtain poly((Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate-polyethylene glycol methyl ether methacrylate). The ninth solvent can be a tetrahydrofuran solution.

[0041] Step S2: Poly((Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate-polyethylene glycol methyl ether methacrylate) is dissolved in water to obtain a copolymer solution. The copolymer solution is irradiated under a UV lamp with a wavelength of 365 nm for 6-12 h and then lyophilized to obtain fluorescent single-chain polymer nanoparticles.

[0042] In this embodiment, a random copolymer was obtained by copolymerizing hydrophobic cyanostilbene methacrylate monomer with hydrophilic polyethylene glycol monomethyl ether methacrylate monomer. In the single-chain aggregated state of this random copolymer, the hydrophobic cyanostilbene moieties can simultaneously exhibit both ordered stacking and monomolecular dispersion. The ordered stacked cyanostilbene moieties undergo intermolecular [2+2] cycloaddition under light irradiation, achieving intramolecular crosslinking of the polymer chain. Meanwhile, the dispersed cyanostilbene moieties undergo intramolecular cyclization under light irradiation, producing phenanthrene derivatives with strong fluorescence properties. Therefore, a one-step method for preparing fluorescent polymer single-chain nanoparticles was achieved. This one-step method for preparing fluorescent polymer single-chain nanoparticles can not only simulate the structural and functional changes during protein folding, but also demonstrates the molecular folding of fluorescent single-chain polymer nanoparticles. Figure 1 ,from Figure 1It can be seen that the synthesized copolymer first collapses in water to form loose nanospheres. Under the irradiation of a 365 nm ultraviolet lamp, the ordered stacked cyanostyrene units undergo intermolecular [2+2] cycloaddition under light conditions, which can realize intramolecular crosslinking of polymer chains. Meanwhile, the dispersed cyanostyrene units undergo intramolecular cyclization under light conditions to produce phenanthrene derivatives with strong fluorescence properties, thus successfully preparing highly fluorescent single-chain polymer nanoparticles.

[0043] The preparation method of cyanostilbene methacrylate monomer in step S1 specifically includes the following steps:

[0044] Step S11: 3,4,5-trihydroxybenzaldehyde, 1-bromododecane, tetrabutylammonium iodide, and potassium carbonate in a molar ratio of 1:3:0.1:(3~1):5:0.2:8 are dissolved in a first solvent, and the mixture is stirred to carry out the first substitution reaction at a temperature of 80~85℃ for 12-24h. After the reaction solution is cooled to room temperature, the product is obtained, and the product of the substitution reaction is purified. The specific process is as follows: N,N-dimethylformamide solvent is removed by low-pressure evaporation, followed by extraction with dichloromethane, then drying with anhydrous magnesium sulfate, followed by rotary evaporation to remove the solvent, and then separation and purification by column chromatography to obtain a white solid 3,4,5-tris(dodecyloxy)benzaldehyde. The first solvent can be an N,N-dimethylformamide solution.

[0045] In bromoalkanes, the bromine atom is readily replaced by other polar groups under polar conditions (such as an alkaline environment). Because the bromine atom has a strong electron-attracting ability, the C-Br bond possesses a certain degree of polarity. When this polar bond encounters the hydroxyl group of 3,4,5-trihydroxybenzaldehyde, the bromine atom can be replaced by the hydroxyl group. Potassium carbonate provides the alkaline environment, and tetrabutylammonium iodide acts as a phase transfer catalyst. If the ratio of 1-bromododecane to 3,4,5-trihydroxybenzaldehyde is less than 3:1, the hydroxyl group will not be completely replaced, easily yielding mono- or di-substituted products.

[0046] In step S12, 3,4,5-tris(dodecyloxy)benzaldehyde and lithium aluminum hydride, in a molar ratio of 1:1~2, are dissolved in a second solvent to obtain a 3,4,5-tris(dodecyloxy)benzaldehyde solution and a lithium aluminum hydride solution. The lithium aluminum hydride solution is slowly added dropwise to the above benzaldehyde derivative solution at -5~5℃ and stirred to carry out the reduction reaction. During the reaction, the mixture is first stirred in an ice bath for 0.5~1h, and then stirred at room temperature for 2~3h. After the reaction is completed, water is added to quench the reaction and the mixture is purified. The specific process is as follows: the second solvent is removed by low-pressure distillation, followed by extraction with dichloromethane, then drying with anhydrous magnesium sulfate and rotary evaporation to remove the solvent, and then separation and purification by column chromatography to obtain a white solid 3,4,5-tris(dodecyloxy)benzyl alcohol. The second solvent can be a tetrahydrofuran solution.

[0047] In this process, the carbonyl group of the benzaldehyde derivative first undergoes a nucleophilic addition reaction with a hydroxide ion to form a benzyl alcohol anion intermediate. Subsequently, the hydride anion transfers from lithium aluminum hydride to the benzyl alcohol anion intermediate, forming benzyl alcohol and a lithium salt. Lithium aluminum hydride acts as a basic reducing agent. If the ratio is less than 1:1, the benzaldehyde derivative cannot be completely reduced; if the ratio is greater than 1:2, benzaldehyde is easily over-reduced, generating byproducts such as methyl compounds.

[0048] In step S13, 3,4,5-tris(dodecyloxy)benzyl alcohol and phosphorus tribromide in a molar ratio of 1:1~2 are dissolved in a third solvent to obtain 3,4,5-tris(dodecyloxy)benzyl alcohol solution and phosphorus tribromide solution, respectively. The phosphorus tribromide solution is slowly added dropwise to the above benzyl alcohol derivative solution at -5~5℃, and the reaction is stirred to carry out the second substitution reaction at room temperature for 3~4 hours. After the reaction is completed, water is added to quench the reaction and the solution is purified. The specific process is as follows: the reaction solution after adding water is extracted with dichloromethane, then dried with anhydrous magnesium sulfate and the solvent is removed by rotary evaporation. The solution is then purified by column chromatography to obtain a white solid 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene. The third solvent can be a dichloromethane solution.

[0049] In this process, the hydroxyl group of the benzyl alcohol derivative is replaced by a bromine atom to form bromobenzene. Phosphorus tribromide serves as both a bromine donor and a catalyst.

[0050] In step S14, 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene, trimethylcyanosilane, and tetrabutylammonium fluoride in a molar ratio of 1:1.2:(0.2-1):1.5:1.5 are dissolved in a fourth solvent, and the first nucleophilic substitution reaction is carried out by stirring at room temperature for 3-4 h. After the reaction, purification is performed. The specific process is as follows: the fourth solvent is removed first, followed by extraction with dichloromethane, then drying with anhydrous magnesium sulfate, followed by rotary evaporation to remove the solvent, and then separation and purification by column chromatography to obtain a white solid 3,4,5-tris(dodecyloxy)phenylacetonitrile. The fourth solvent can be acetonitrile.

[0051] In this process, tetrabutylammonium fluoride releases fluoride ions, which break the carbon-silicon bond and activate trimethylcyanosilane to release cyanide ions. The cyanide ions then undergo an SN2 nucleophilic substitution reaction with bromobenzene, where the bromine is replaced by the cyano group, generating a phenylacetonitrile derivative. Trimethylcyanosilane provides the cyano group, and tetrabutylammonium fluoride acts as a phase transfer catalyst.

[0052] Step S15: Dissolve tetraethylene glycol and triethylamine in a fifth solvent to obtain a first mixed solution. Dissolve 4-toluenesulfonyl chloride in the fifth solvent to obtain a 4-toluenesulfonyl chloride solution. Add the 4-toluenesulfonyl chloride solution dropwise to the first mixed solution at -5 to 5°C. The molar ratio of tetraethylene glycol, 4-toluenesulfonyl chloride, and triethylamine dissolved in dichloromethane is 1:1:(1.1~4):1:1.2. After the addition is complete, continue stirring at room temperature to carry out the second nucleophilic substitution reaction (SN2) for 0.5~1 h. After the reaction is completed, purification is carried out. The specific process is as follows: add sodium bicarbonate to neutralize the pH, extract with dichloromethane, dry with anhydrous magnesium sulfate, remove the solvent by rotary evaporation, and then separate and purify by column chromatography to obtain an oily liquid p-toluenesulfonate-tetraethylene glycol. The fifth solvent can be a dichloromethane solution.

[0053] In this process, the hydroxyl group of tetraethylene glycol acts as a nucleophile, attacking the sulfur atom of 4-toluenesulfonyl chloride to generate p-toluenesulfonate-tetraethylene glycol, while triethylamine acts as a base to capture the byproduct hydrogen chloride, preventing acidification of the system. Since tetraethylene glycol has two hydroxyl sites, it needs to be in excess to achieve monohydroxyl esterification.

[0054] Step S16: p-Toluenesulfonate-tetraethylene glycol, p-hydroxybenzaldehyde, and potassium carbonate in a molar ratio of 1:1:(2~1.1):1:3 are dissolved in the sixth solvent and stirred to carry out the first nucleophilic addition reaction. The reaction temperature is 80~85℃ and the reaction time is 12~24h. After the reaction solution is cooled to room temperature, it is purified. The specific process is as follows: the sixth solvent is removed, followed by extraction with dichloromethane, then drying with anhydrous magnesium sulfate, and then removing the solvent by rotary evaporation. Finally, the solution is purified by column chromatography to obtain an oily liquid 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde. The sixth solvent can be N,N-dimethylformamide solution.

[0055] In this process, the hydroxyl group acts as a nucleophile to attack the carbonyl carbon of p-toluenesulfonate, forming an intermediate, and then the sulfonate group is released as a leaving group.

[0056] Step S17: Dissolve 3,4,5-tris(dodecyloxy)phenylacetonitrile and 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde in a seventh solvent (a mixture of ethanol and tetrabutylammonium hydroxide in a volume ratio of 20-30:1) at a molar ratio of 1-1.2:1. Stir to carry out the second nucleophilic addition reaction and dehydration reaction at a temperature of 40-50°C for 12-24 hours. After the reaction, purification is performed. The specific process is as follows: first, the seventh solvent is removed, followed by extraction with dichloromethane, then drying with anhydrous magnesium sulfate, followed by rotary evaporation to remove the solvent, and finally purification by column chromatography to obtain a yellow solid (Z)-3-(4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)phenyl) -2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile; wherein, the seventh solvent can be a mixed solution of ethanol and tetrabutylammonium hydroxide, wherein the volume ratio of ethanol to tetrabutylammonium hydroxide is 20~30:1.

[0057] In this process, the carbon atom near the alkynyl hydrogen atom in the phenylacetonitrile derivative acts as a nucleophile to attack the carbonyl carbon in the benzaldehyde derivative, forming a four-membered ring intermediate. The intermediate then undergoes a dehydration reaction (generating one molecule of water) to form a double bond in cyanostilbene, a process involving the removal of hydroxide ions.

[0058] Step S18: Dissolve (Z)-3-(4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)phenyl)-2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile and triethylamine in the eighth solvent to obtain a second mixed solution; dissolve methacryloyl chloride in the eighth solvent to obtain a methacryloyl chloride solution; (Z)-3-(4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)phenyl) The molar ratio of -2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile, methacryloyl chloride, and triethylamine is 1:3:3. A methacryloyl chloride solution is slowly added dropwise to the above acrylonitrile derivative solution at -5 to 5°C. After the addition is complete, the mixture is stirred at room temperature for 12 hours to carry out the third nucleophilic substitution reaction. After the reaction is complete, the reaction is quenched with water and then purified. The specific process is as follows: extraction with dichloromethane, drying with anhydrous magnesium sulfate, rotary evaporation to remove the solvent, and then separation and purification by column chromatography to obtain a yellow solid (Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate, i.e., cyanostilbene methacrylate monomer. The eighth solvent can be dichloromethane solution. The structural formula of the cyanostilbene methacrylate monomer is:

[0059]

[0060] A second embodiment of the present invention provides the application of fluorescent single-chain polymer nanoparticles in catalysts, biosensors, nanoreactors, or nanomedicines.

[0061] Example 1

[0062] In step S10, 1.8 g of methyl 3,4,5-trihydroxybenzoate, 9.74 g of 1-bromododecane, 0.1 g of tetrabutylammonium iodide, 10.7 g of K2CO3, and 50 mL of N,N-dimethylformamide were added to a 100 mL round-bottom flask and stirred overnight at a constant temperature of 80 °C. After the reaction was completed and cooled to room temperature, most of the N,N-dimethylformamide solvent was removed by vacuum distillation. Then, the mixture was extracted 2-3 times with 50 mL of dichloromethane, dried over anhydrous magnesium sulfate, and the solvent was removed by rotary evaporation. The mixture was then purified by column chromatography (eluent: hexane: ethyl acetate = 5:1) to obtain a purified white solid, 3,4,5-tris(dodecyloxy)benzaldehyde.

[0063] Step S20: Add 6.2 g of 3,4,5-trihydroxybenzaldehyde and 20 mL of tetrahydrofuran to a reaction flask. Stir at 0 °C for 20 min. Then, add 13 mL of a lithium aluminum hydride tetrahydrofuran solution to a constant pressure dropping funnel and slowly add it dropwise to a round-bottom flask (controlling the dropping time to 1 h). Continue stirring in an ice bath for 30 min, then transfer to room temperature and continue stirring for 2 h. Monitor the reaction progress using thin-layer chromatography. After the reaction is complete, slowly add a small amount of water to quench it, and remove most of the solvent by vacuum distillation. Extract three times with dichloromethane, then dry with anhydrous magnesium sulfate and remove the solvent by rotary evaporation. Collect the clean product as a white solid, 3,4,5-tris(dodecyloxy)benzyl alcohol.

[0064] Step S30: Add 4.2 g of 3,4,5-tris(dodecyloxy)benzyl alcohol and 20 mL of dichloromethane to a round-bottom flask, stir at 0°C for 20 min, add 1.4 mL of phosphorus tribromide tetrahydrofuran solution to a constant pressure dropping funnel, and slowly add it dropwise to the round-bottom flask, controlling the addition time to 2 h. After the addition is complete, transfer to room temperature and continue stirring for 3 h. Monitor the reaction progress by thin-layer chromatography. After the reaction is complete, slowly add a small amount of water to quench it, extract twice with dichloromethane, then dry with anhydrous magnesium sulfate and remove the solvent by rotary evaporation to obtain a white solid 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene;

[0065] In step S40, 3.7 g of 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene, 30 mL of acetonitrile, and 1.2 mL of trimethylcyanosilane were added to a round-bottom flask and stirred at room temperature for 3 h. The reaction progress was monitored by thin-layer chromatography. After the reaction was completed, most of the solvent was removed by vacuum distillation, and the mixture was extracted twice with dichloromethane. Then, the mixture was dried over anhydrous magnesium sulfate and the solvent was removed by rotary evaporation. Finally, the mixture was purified by column chromatography (eluent: dichloromethane) to obtain a white solid, 3,4,5-tris(dodecyloxy)phenylacetonitrile.

[0066] In step S50, 6 g of tetraethylene glycol, 3.9 mL of triethylamine, and 20 mL of dichloromethane were added to a round-bottom flask and stirred at 0°C for 20 min. 1.47 g of 4-toluenesulfonyl chloride and 20 mL of dichloromethane solution were added to a constant-pressure dropping funnel and slowly added dropwise to the round-bottom flask over a time of 30 min. After the addition was complete, stirring was continued at room temperature for 0.5–1 h. After the reaction was complete, sodium bicarbonate was added, and the mixture was extracted twice with dichloromethane. The solvent was then removed by rotary evaporation after drying with anhydrous magnesium sulfate, followed by column chromatography to obtain an oily liquid p-toluenesulfonate-tetraethylene glycol.

[0067] In step S60, 1.57 g of p-toluenesulfonate-tetraethylene glycol, 0.52 g of p-hydroxybenzaldehyde, and 1.19 g of carbonic acid were dissolved in N,N-dimethylformamide and stirred overnight at 85°C. After the reaction solution was cooled to room temperature, the N,N-dimethylformamide solvent was removed by low-pressure evaporation, followed by extraction with dichloromethane three times, drying with anhydrous magnesium sulfate, and then removing the solvent by rotary evaporation. The solution was then purified by column chromatography to obtain an oily liquid 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde.

[0068] Step S70: 0.5 g of 3,4,5-tris(dodecyloxy)phenylacetonitrile, 30 mL of a 25:1 mixture of ethanol and tetrabutylammonium hydroxide were added to a round-bottom flask. The mixture was slowly heated to 50°C until it was completely dissolved and clarified. Then, 1.12 g of 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde was added and the mixture was stirred at 40°C overnight. After the reaction was completed, the solvent was removed by low-pressure distillation, followed by extraction with dichloromethane three times. The mixture was then dried over anhydrous magnesium sulfate and the solvent was removed by rotary evaporation. Finally, the mixture was purified by column chromatography to obtain a yellow solid (Z)-3-(4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)phenyl)-2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile.

[0069] In step S80, 1.18 g of (Z)-3-(4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)phenyl)-2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile, 0.52 ml of triethylamine, and 30 mL of anhydrous dichloromethane were dissolved in a solution. 0.39 g of methacryloyl chloride and 30 mL of anhydrous dichloromethane were added to a constant-pressure dropping funnel and slowly added dropwise to a round-bottom flask over 8 hours. After addition, the mixture was stirred overnight at room temperature. After the reaction was complete, water was added to quench the reaction. The mixture was extracted three times with dichloromethane, dried over anhydrous magnesium sulfate, and the solvent was removed by rotary evaporation. The mixture was then purified by column chromatography to obtain a yellow solid (Z)-2-(2-(2-(2-(4-(2-cyano-2- (3,4,5-Tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate.

[0070] Example 2

[0071] In step S90, 0.12 g of polyethylene glycol methyl ether methacrylate, 0.1 g of (Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate and 0.01 g of AIBN were dissolved in tetrahydrofuran solution. The mixed solution was subjected to three freeze-vacuum-thaw cycles in a dry Schlenk tube under nitrogen atmosphere, followed by stirring at 75°C for 12 h. After the reaction was completed, the mixture was purified by column chromatography to obtain a viscous yellow water-soluble copolymer, namely poly((Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethyl methacrylate-polyethylene glycol methyl ether methacrylate).

[0072] In step S100, 1 g of the water-soluble copolymer prepared in step S90 is dissolved in 1 mL of ultrapure water and sonicated until the solution is clear. Then, the solution is transferred to a 365 nm ultraviolet lamp and irradiated at room temperature for 6 h. After freeze-drying, viscous yellow solid fluorescent single-chain polymer nanoparticles are obtained, with x=0.8 and y=0.2 in their chemical formula.

[0073] The atomic force microscope image of the fluorescent single-chain polymer nanoparticles prepared in this embodiment is shown below. Figure 2 As can be seen from the figure, single-chain polymer nanoparticles have been successfully obtained in this embodiment; and the products obtained in this embodiment were compared by gel permeation chromatography, and the results are shown in the figure. Figure 3 ,from Figure 3 As can be seen, this embodiment has successfully obtained single-chain polymer nanoparticles. From Figure 4As can be seen from the graph showing the change in fluorescence intensity over irradiation time, the single-chain polymer nanoparticles prepared in Example 1 exhibit strong green light emission.

[0074] Example 3

[0075] Step S10: 2 g of methyl 3,4,5-trihydroxybenzoate, 12.2 g of 1-bromododecane, 0.6 g of tetrabutylammonium iodide, 7.6 g of K2CO3, and 50 mL of N,N-dimethylformamide were added to a 100 mL round-bottom flask and stirred overnight at a constant temperature of 85 °C. After the reaction was completed and cooled to room temperature, most of the N,N-dimethylformamide solvent was removed by vacuum distillation. Then, the mixture was extracted 2-3 times with 50 mL of dichloromethane, dried over anhydrous magnesium sulfate, and the solvent was removed by rotary evaporation. Finally, the mixture was purified by column chromatography (eluent: hexane: ethyl acetate = 5:1) to obtain a purified white solid, 3,4,5-tris(dodecyloxy)benzaldehyde.

[0076] Step S20: Add 7 g of 3,4,5-trihydroxybenzaldehyde and 20 mL of tetrahydrofuran to a reaction flask. Stir at 0 °C for 20 min. Then, add 45 mg of a tetrahydrofuran solution of lithium aluminum hydride to a constant pressure dropping funnel and slowly add it dropwise to a round-bottom flask (controlling the dropping time to 1 h). Continue stirring in an ice bath for 1 h, then transfer to room temperature and continue stirring for 3 h. Monitor the reaction progress using thin-layer chromatography. After the reaction is complete, slowly add a small amount of water to quench it, and remove most of the solvent by vacuum distillation. Extract three times with dichloromethane, then dry with anhydrous magnesium sulfate and remove the solvent by rotary evaporation. Collect the clean product as a white solid, 3,4,5-tris(dodecyloxy)benzyl alcohol.

[0077] In step S30, 10 g of 3,4,5-tris(dodecyloxy)benzyl alcohol and 20 mL of dichloromethane were added to a round-bottom flask and stirred at 0°C for 20 min. Then, 2.1 mL of a tetrahydrofuran solution of phosphorus tribromide was added to a constant-pressure dropping funnel and slowly added dropwise to the round-bottom flask over a time of 2.5 h. After the addition was complete, the mixture was transferred to room temperature and stirred for another 4 h. The reaction progress was monitored by thin-layer chromatography. After the reaction was complete, a small amount of water was slowly added to quench the reaction. The mixture was extracted twice with dichloromethane, dried over anhydrous magnesium sulfate, and the solvent was removed by rotary evaporation to obtain a white solid, 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene.

[0078] In step S40, 4.1 g of 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene and 30 mL of acetonitrile were added to a round-bottom flask and dissolved completely. Then, 0.85 mL of trimethylcyanosilane and 0.3 g of tetrabutylammonium fluoride were added dropwise to the round-bottom flask, and the mixture was stirred at room temperature for 5 h. The reaction progress was monitored by thin-layer chromatography. After the reaction was completed, most of the solvent was removed by vacuum distillation, and the mixture was extracted twice with dichloromethane. Then, the mixture was dried over anhydrous magnesium sulfate and the solvent was removed by rotary evaporation. Finally, the mixture was purified by column chromatography (eluent: dichloromethane) to obtain a white solid, 3,4,5-tris(dodecyloxy)phenylacetonitrile.

[0079] In step S50, 6 g of tetraethylene glycol, 1.57 mL of triethylamine, and 20 mL of dichloromethane were added to a round-bottom flask and stirred at 0°C for 20 min. Then, 1.95 g of 4-toluenesulfonyl chloride and 20 mL of dichloromethane solution were added to a constant pressure dropping funnel and slowly added dropwise to the round-bottom flask over a period of 2 h. After the addition was complete, stirring was continued at room temperature for 0.5–1 h. After the reaction was complete, sodium bicarbonate was added, and the mixture was extracted twice with dichloromethane. The solvent was then removed by rotary evaporation after drying with anhydrous magnesium sulfate, followed by column chromatography to obtain an oily liquid p-toluenesulfonate-tetraethylene glycol.

[0080] In step S60, 1.5 g of p-toluenesulfonate-tetraethylene glycol, 0.45 g of p-hydroxybenzaldehyde, and 1.55 g of carbonic acid were dissolved in N,N-dimethylformamide and stirred overnight at 80°C. After the reaction solution was cooled to room temperature, the N,N-dimethylformamide solvent was removed by low-pressure evaporation, followed by extraction with dichloromethane three times. Then, the solution was dried over anhydrous magnesium sulfate and the solvent was removed by rotary evaporation. Finally, the solution was purified by column chromatography to obtain an oily liquid 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde.

[0081] Step S70: 0.5 g of 3,4,5-tris(dodecyloxy)phenylacetonitrile, 30 mL of ethanol and tetrabutylammonium hydroxide (25:1) mixed solvent were added to a round-bottom flask. The mixture was slowly heated to 50 °C until it was completely dissolved and clarified. 0.94 g of 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde was added and the mixture was stirred at 45 °C overnight. After the reaction was completed, the solvent was removed by low-pressure distillation, followed by extraction with dichloromethane three times. The mixture was then dried over anhydrous magnesium sulfate and the solvent was removed by rotary evaporation. The mixture was then purified by column chromatography to obtain a yellow solid (Z)-3-(4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)phenyl)-2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile.

[0082] In step S80, 1.18 g of (Z)-3-(4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)phenyl)-2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile, 0.52 ml of triethylamine, and 30 mL of anhydrous dichloromethane were dissolved in a solution. 0.32 g of methacryloyl chloride and 30 mL of anhydrous dichloromethane were added to a constant-pressure dropping funnel and slowly added dropwise to a round-bottom flask over 8 hours. After addition, the mixture was stirred overnight at room temperature. After the reaction was complete, water was added to quench the reaction. The mixture was extracted three times with dichloromethane, dried over anhydrous magnesium sulfate, and the solvent was removed by rotary evaporation. The mixture was then purified by column chromatography to obtain a yellow solid (Z)-2-(2-(2-(2-(4-(2-cyano-2- (3,4,5-Tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate.

[0083] Example 4

[0084] In step S90, 0.09 g of polyethylene glycol methyl ether methacrylate, 0.15 g of (Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate and 0.007 g of AIBN were dissolved in tetrahydrofuran solution. The mixed solution was subjected to three freeze-vacuum-thaw cycles in a dry Schlenk tube under nitrogen atmosphere, followed by stirring at 70°C for 20 h. After the reaction was completed, the mixture was purified by column chromatography to obtain a viscous yellow water-soluble copolymer, namely poly((Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethyl methacrylate-polyethylene glycol methyl ether methacrylate).

[0085] In step S100, 1 g of the water-soluble copolymer prepared in step S90 is dissolved in 1 mL of ultrapure water and sonicated until the solution is clear. Then, the solution is transferred to a 365 nm ultraviolet lamp and irradiated at room temperature for 12 h. After freeze-drying, viscous yellow solid fluorescent single-chain polymer nanoparticles are obtained, with x=0.67 and y=0.33 in their chemical formula.

[0086] Example 5

[0087] In step S90, 0.2 g of polyethylene glycol methyl ether methacrylate, 0.12 g of (Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate and 0.014 g of AIBN were dissolved in tetrahydrofuran solution. The mixed solution was subjected to three freeze-vacuum-thaw cycles in a dry Schlenk tube under nitrogen atmosphere, followed by stirring at 80°C for 6 h. After the reaction was completed, the mixture was purified by column chromatography to obtain a viscous yellow water-soluble copolymer, namely poly((Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethyl methacrylate-polyethylene glycol methyl ether methacrylate).

[0088] In step S100, 1 g of the water-soluble copolymer prepared in step S90 is dissolved in 1 mL of ultrapure water and sonicated until the solution is clear. Then, the solution is transferred to a 365 nm ultraviolet lamp and irradiated at room temperature for 4 h. After freeze-drying, viscous yellow solid fluorescent single-chain polymer nanoparticles are obtained, with x=0.86 and y=0.14 in their chemical formula.

[0089] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A fluorescent single-chain polymer nanoparticle, characterized in that, The fluorescent single-chain polymer nanoparticles were obtained by irradiating a solution of a copolymer having the following structural formula under a UV lamp and then separating it by freeze-drying. The structural formula of the copolymer is: ； In the aforementioned structural formula, x + y = 1.

2. A one-step preparation method for fluorescent single-chain polymer nanoparticles according to claim 1, characterized in that, include: Polyethylene glycol methyl ether methacrylate, cyanostilbene methacrylate monomers and an initiator were dissolved in a ninth solvent to obtain a reaction solution. The reaction solution was then subjected to a polymerization reaction under a nitrogen atmosphere to obtain poly((Z)-2-(2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate-polyethylene glycol methyl ether methacrylate); The copolymer solution was obtained by dissolving the poly((Z)-2-(2-(2-(4-(2-cyano-2-(3,4,5-tris(dodecyloxy)phenyl)vinyl)hydroxyethoxy)ethoxy)ethoxy)ethoxy)ethyl methacrylate-polyethylene glycol methyl ether methacrylate) in water. The copolymer solution was then irradiated under a UV lamp and lyophilized to obtain fluorescent single-chain polymer nanoparticles.

3. The one-step preparation method of fluorescent single-chain polymer nanoparticles according to claim 2, characterized in that, The preparation method of the cyanostilbene methacrylate monomer includes: 3,4,5-trihydroxybenzaldehyde, 1-bromododecane, tetrabutylammonium iodide and potassium carbonate were dissolved in a first solvent and subjected to a first substitution reaction to obtain 3,4,5-tris(dodecyloxy)benzaldehyde. 3,4,5-tris(dodecyloxy)benzaldehyde was dissolved in a second solvent to obtain a 3,4,5-tris(dodecyloxy)benzaldehyde solution. A lithium aluminum hydride solution was added dropwise to the 3,4,5-tris(dodecyloxy)benzaldehyde solution, and a reduction reaction was carried out to obtain 3,4,5-tris(dodecyloxy)benzyl alcohol. 3,4,5-tris(dodecyloxy)benzyl alcohol was dissolved in a third solvent to obtain a 3,4,5-tris(dodecyloxy)benzyl alcohol solution. Phosphorus tribromide solution was added dropwise to the 3,4,5-tris(dodecyloxy)benzyl alcohol solution, and a second substitution reaction was carried out to obtain 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene. The 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene, trimethylcyanosilane and tetrabutylammonium fluoride are dissolved in a fourth solvent and undergo a first nucleophilic substitution reaction to give 3,4,5-tris(dodecyloxy)phenylacetonitrile; Triethylene glycol and triethylamine were dissolved in a fifth solvent to obtain a first mixed solution. A 4-toluenesulfonyl chloride solution was added dropwise to the first mixed solution, and a second nucleophilic substitution reaction was carried out to obtain p-toluenesulfonate-tetraethylene glycol. The p-toluenesulfonate-tetraethylene glycol, p-hydroxybenzaldehyde, and carbonic acid were dissolved in a sixth solvent and subjected to a first nucleophilic addition reaction to obtain 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde; The 3,4,5-tris(dodecyloxy)phenylacetonitrile and the 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde were dissolved in a seventh solvent and subjected to a second nucleophilic addition reaction and a dehydration reaction to obtain (Z)-3-(4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)phenyl)-2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile; The (Z)-3-(4-(2-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)phenyl)-2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile and triethylamine were dissolved in an eighth solvent to obtain a second mixed solution. A methacryloyl chloride solution was added dropwise to the second mixed solution, and a third nucleophilic substitution reaction was carried out to obtain the cyanostilbene methacrylate monomer.

4. The one-step preparation method of fluorescent single-chain polymer nanoparticles according to claim 3, characterized in that, In the first substitution reaction, the molar ratio of 3,4,5-trihydroxybenzaldehyde, 1-bromododecane, tetrabutylammonium iodide and potassium carbonate is 1:3:0.1:(3~1):5:0.2:8, the reaction temperature is 80~85℃, and the reaction time is 12-24h; In the reduction reaction, the molar ratio of 3,4,5-tris(dodecyloxy)benzaldehyde to lithium aluminum hydride in the lithium aluminum hydride solution is 1:1~2, the dropping temperature is -5~5℃, and the reaction conditions are: reacting at -5~5℃ for 0.5~1h and then reacting at 20~30℃ for 2~3h. In the second substitution reaction, the molar ratio of 3,4,5-tris(dodecyloxy)benzyl alcohol to phosphorus tribromide in the phosphorus tribromide solution is 1:1~2, the dropping temperature is -5~5℃, the reaction temperature is 20~30℃, and the reaction time is 3~4h; In the first nucleophilic substitution reaction, the molar ratio of 5-(bromomethyl)-1,2,3-tris(dodecyloxy)benzene, trimethylcyanosilane and tetrabutylammonium fluoride is 1:1.2:(0.2~1):1.5:1.5, the reaction temperature is 20~30℃, and the reaction time is 3~4h.

5. The one-step preparation method of fluorescent single-chain polymer nanoparticles according to claim 3, characterized in that, In the second nucleophilic substitution reaction, the molar ratio of 4-toluenesulfonyl chloride, tetraethylene glycol and triethylamine in the reaction solution is 1:1:(1.1~4):1:1.2, the dropping temperature is -5~5℃, the reaction temperature is 20~30℃, and the reaction time is 0.5~1h; In the first nucleophilic addition reaction, the molar ratio of p-toluenesulfonate-tetraethylene glycol, p-hydroxybenzaldehyde and carbonic acid is 1:1:(2~1.1):1:3, the reaction temperature is 80~85℃, and the reaction time is 12~24h; In the second nucleophilic addition reaction, the molar ratio of 3,4,5-tris(dodecyloxy)phenylacetonitrile and 4-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)ethoxy)benzaldehyde is 1~1.2:1, the reaction temperature is 40~50℃, and the reaction time is 12~24h; In the third nucleophilic substitution reaction, the molar ratio of (Z)-3-(4-(2-(2-(2-(2-(2-hydroxyethoxy)ethoxy)ethoxy)phenyl)-2-(3,4,5-tris(dodecyloxy)phenyl)acrylonitrile, the triethylamine, and the methacryloyl chloride solution in the methacryloyl chloride solution is 1:1:(1.5~1):3:3, the dropping temperature is -5~5℃, the reaction temperature is 20~30℃, and the reaction time is 12~24h.

6. The one-step preparation method of fluorescent single-chain polymer nanoparticles according to claim 3, characterized in that, The first solvent is N,N-dimethylformamide solution, the second solvent is tetrahydrofuran solution, the third solvent is dichloromethane solution, and the fourth solvent is acetonitrile; The fifth solvent is a dichloromethane solution, the sixth solvent is an N,N-dimethylformamide solution, the seventh solvent is a mixed solution of ethanol and tetrabutylammonium hydroxide, wherein the volume ratio of ethanol to tetrabutylammonium hydroxide is 20~30:1, and the eighth solvent is a dichloromethane solution.

7. The one-step preparation method of fluorescent single-chain polymer nanoparticles according to claim 2, characterized in that, Before the polymerization reaction, the reaction solution is subjected to a freeze-vacuum-thaw cycle in a nitrogen atmosphere; and after the polymerization reaction, the reaction products are separated and purified.

8. The one-step preparation method of fluorescent single-chain polymer nanoparticles according to claim 2, characterized in that, The polymerization reaction is carried out at a temperature of 73-76°C for 10-12 hours; the ninth solvent is a tetrahydrofuran solution; and the ultraviolet lamp has a wavelength of 365 nm and an irradiation time of 6-12 hours.

9. An application of the fluorescent single-chain polymer nanoparticles according to claim 1 in catalysts, biosensors, nanoreactors, or nanomedicines.

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