2D fluorescent flaky micelle and preparation method thereof

Abstract

The invention relates to a 2D fluorescent flaky micelle and a preparation method thereof. The preparation method comprises the following steps: (1) synthesizing a block copolymer PCL-b-PDMA, a homopolymer PCL-SP and a homopolymer PCL-FL; (2) preparation of 1D seed micelles; dissolving the block copolymer PCL-b-PDMA in absolute ethyl alcohol, heating, cooling to room temperature, aging to obtain a polydisperse 1D cylindrical micelle solution, and placing the polydisperse 1D cylindrical micelle solution in an ice-water bath for ultrasonic treatment to obtain a monodisperse 1D cylindrical seed micelle solution; (3) preparing a 2D fluorescent flaky micelle; on the basis of PCL-b-PDMA, PCL-SP and PCL-FL, generating a 2D single-layer fluorescent flaky micelle or a 2D two-layer fluorescent flaky micelle in the seed micelle solution obtained in the step (2). According to the invention, the 2D fluorescent flaky micelle with controllable morphology and uniform size is successfully prepared, and a new scheme is provided for preparing a complex micelle with a fluorescent structure through crystal-driven self-assembly.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and in particular relates to a 2D fluorescent lamellar micelle and a preparation method thereof. Background Art

[0002] Self-assembly of block copolymers is an effective means to prepare soft matter two-dimensional nanomaterials, and the functional two-dimensional nanomaterials prepared are widely used in various fields. The performance of two-dimensional nanomaterials is not only related to the composition of the material, but also closely related to its size and structure. The preparation of two-dimensional nanomaterials with regular morphology, controllable size and adjustable structure has always been an important issue in the field of self-assembly. At present, in the field of polymers, it is difficult to control the morphology of the prepared micelles by self-assembly of amorphous block copolymers, while the solution self-assembly of crystalline block copolymers can achieve precise control of the micelle morphology through the dual effects of crystallization force and hydrophilic and hydrophobic properties. Introducing organic dyes into the crystalline core to prepare 2D fluorescent lamellar micelles with regular morphology is rarely involved in this part of the research content. Therefore, how to prepare 2D fluorescent lamellar micelles with regular morphology still needs in-depth research. Summary of the invention

[0003] Based on the above-mentioned shortcomings and deficiencies in the prior art, one of the objects of the present invention is to at least solve one or more of the above-mentioned problems in the prior art. In other words, one of the objects of the present invention is to provide a 2D multilayer fluorescent lamellar micelle and a preparation method thereof that meet one or more of the above-mentioned needs.

[0004] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0005] A method for preparing 2D fluorescent lamellar micelles comprises the following steps:

[0006] (1) Synthesis of block copolymer PCL-b-PDMA, homopolymer PCL-SP, and homopolymer PCL-FL;

[0007] Wherein, the structural formula of the block copolymer PCL-b-PDMA is:

[0008]

[0009] Wherein, X is an integer between 40 and 60, and Y is an integer between 100 and 300;

[0010] The structural formula of the homopolymer PCL-SP is:

[0011]

[0012] Wherein, Z is an integer between 40 and 60;

[0013] The structural formula of the homopolymer PCL-FL is:

[0014]

[0015] Wherein, Z is an integer between 40 and 60;

[0016] (2) Preparation of 1D seed micelles;

[0017] The block copolymer PCL-b-PDMA was dissolved in anhydrous ethanol, and after heating treatment, cooled to room temperature and aged to obtain a polydisperse 1D cylindrical micelle solution, which was then ultrasonically treated in an ice-water bath to obtain a monodisperse 1D cylindrical seed micelle solution;

[0018] (3) Preparation of 2D fluorescent lamellar micelles;

[0019] Based on the block copolymer PCL-b-PDMA, homopolymer PCL-SP, and homopolymer PCL-FL, 2D single-layer fluorescent lamellar micelles or 2D two-layer fluorescent lamellar micelles are generated in the seed micelle solution obtained in step (2).

[0020] As a preferred solution, the step (3) specifically comprises:

[0021] A PCL-SP / PCL-FL / PCL-b-PDMA monomer mixed with homopolymer PCL-SP, homopolymer PCL-FL and block copolymer PCL-b-PDMA is dissolved in a good solvent and then added dropwise to the seed micelle solution obtained in step (2) to obtain a 2D monolayer lamellar micelle in which the PCL-SP / PCL-FL / PCL-b-PDMA monomer is epitaxially grown along the PCL-b-PDMA short crystals.

[0022] As a preferred embodiment, the mass ratio of the homopolymer PCL-SP, the homopolymer PCL-FL and the block copolymer PCL-b-PDMA is 1:(0.003-0.006):1;

[0023] The mass ratio of PCL-SP / PCL-FL / PCL-b-PDMA monomer to the seed micelle in the seed micelle solution is (1-30):1;

[0024] The good solvent is one or more of tetrahydrofuran, chloroform, dimethylformamide, 1,4-dioxane, and dimethyl sulfoxide.

[0025] As a preferred solution, the step (3) specifically comprises:

[0026] Dissolving PCL / PCL-FL / PCL-b-PDMA monomers mixed with PCL, homopolymer PCL-FL and block copolymer PCL-b-PDMA in a good solvent, and then dropping the monomers into the seed micelle solution obtained in step (2) to obtain a 2D monolayer micelle solution;

[0027] Then, the PCL-SP / PCL-b-PDMA monomer, which is a mixture of the homopolymer PCL-SP and the block copolymer PCL-b-PDMA, is dissolved in a good solvent and then added dropwise to the 2D monolayer lamellar micelle solution to obtain 2D two-layer lamellar micelles.

[0028] As a preferred solution, the step (3) specifically comprises:

[0029] Dissolving a PCL-SP / PCL-b-PDMA monomer obtained by mixing a homopolymer PCL-SP and a block copolymer PCL-b-PDMA in a good solvent, and then dropping the monomer into the seed micelle solution obtained in step (2) to obtain a 2D monolayer micelle solution;

[0030] Then, PCL / PCL-FL / PCL-b-PDMA monomers, which are a mixture of PCL, homopolymer PCL-FL and block copolymer PCL-b-PDMA, are dissolved in a good solvent and then added dropwise to the 2D monolayer lamellar micelle solution to obtain 2D two-layer lamellar micelles.

[0031] As a preferred embodiment, the mass ratio of PCL, homopolymer PCL-FL and block copolymer PCL-b-PDMA in the PCL / PCL-FL / PCL-b-PDMA monomer is 1:(0.003-0.006):1;

[0032] The mass ratio of homopolymer PCL-SP and block copolymer PCL-b-PDMA in PCL-SP / PCL-b-PDMA monomer is 1:(0.2-5);

[0033] The mass ratio of PCL-SP / PCL-b-PDMA monomer or PCL / PCL-FL / PCL-b-PDMA monomer to the seed micelle in the seed micelle solution is (1-30):1;

[0034] The good solvent is one or more of tetrahydrofuran, chloroform, dimethylformamide, 1,4-dioxane, and dimethyl sulfoxide.

[0035] As a preferred embodiment, the synthesis of the block copolymer PCL-b-PDMA comprises:

[0036] Small molecule initiators 4-(hydroxymethyl) dodecyl benzyl carbonate, caprolactone, diphenyl phosphate, and toluene were added to the reaction bottle in sequence, stirred at room temperature, precipitated and centrifuged several times in iced methanol, and vacuum dried to obtain the macromolecular initiator PCL-CTA;

[0037] The RAFT polymerization macromolecular initiator PCL-CTA, azobisisobutyronitrile, 1,4-dioxane, and N,N-dimethylacrylamide were added to the reaction bottle in sequence, and after multiple cycles of liquid nitrogen freezing-vacuuming-nitrogen-vacuuming-thawing, the reaction was placed in an oil bath under a nitrogen atmosphere; after the reaction was terminated by rapid cooling with liquid nitrogen, the block copolymer PCL-b-PDMA was obtained by precipitation and centrifugation in iced n-hexane for several times and vacuum drying;

[0038] The molar ratio of the macromolecular initiator PCL-CTA, N,N-dimethylacrylamide and azobisisobutyronitrile is 1:(200-400):(0.1-0.3).

[0039] As a preferred embodiment, the synthesis of the homopolymer PCL-SP comprises:

[0040] Small molecule initiators 4-(hydroxymethyl) dodecyl benzyl carbonate, caprolactone, diphenyl phosphate, and toluene were added to the reaction flask in sequence, stirred at room temperature, precipitated and centrifuged several times in iced methanol, and vacuum dried to obtain the macromolecular initiator PCL-CTA;

[0041] The macroinitiator PCL-CTA, carboxyl spiropyran SP, 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI, 4-dimethylaminopyridine DMAP, and ultra-dry dichloromethane were added into a reaction bottle, stirred at room temperature for several days, and then precipitated with methanol and centrifuged several times to obtain the homopolymer PCL-SP;

[0042] Among them, the molar ratio of the macromolecular initiator PCL-CTA, carboxyl spiropyran SP, 4-dimethylaminopyridine DMAP, and 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI is 1: (1-10): 1: (1-10).

[0043] As a preferred embodiment, the synthesis of the homopolymer PCL-FL comprises:

[0044] Small molecule initiators 4-(hydroxymethyl) dodecyl benzyl carbonate, caprolactone, diphenyl phosphate, and toluene were added to the reaction flask in sequence, stirred at room temperature, precipitated and centrifuged several times in iced methanol, and vacuum dried to obtain the macromolecular initiator PCL-CTA;

[0045] The macroinitiator PCL-CTA, carboxyl rhodamine FL, 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI, 4-dimethylaminopyridine DMAP, and ultra-dry dichloromethane were added to a reaction bottle, stirred at room temperature for 3 days, and then precipitated with methanol and centrifuged three times to obtain a homopolymer PCL-FL;

[0046] Among them, the molar ratio of the macromolecular initiator PCL-CTA, carboxyrhodamine FL, 4-dimethylaminopyridine DMAP, and 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI is (0.8-1):1:1:(1-10).

[0047] The present invention also provides 2D fluorescent lamellar micelles prepared by the preparation method described in any of the above schemes.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] The present invention can obtain 1D cylindrical seed micelles of uniform size by ultrasonically interrupting polydisperse 1D cylindrical micelles, and the seed micelles still retain terminal activity; then after adding monomers, they can be assembled into 2D single-layer hexagonal fluorescent lamellar micelles under the drive of homopolymer PCL; then, the new monomers are added to the 2D single-layer hexagonal fluorescent lamellar micelles, which can achieve epitaxial growth of the monomers on their periphery, and successfully prepare 2D multilayer fluorescent lamellar micelles with controllable morphology and uniform size, providing a new solution for crystallization-driven self-assembly to prepare micelles with complex fluorescent structures.

[0050] The preparation method of the 2D fluorescent lamellar micelles of the present invention is simple to operate and has mild preparation conditions. The prepared 2D fluorescent lamellar micelles have regular shapes and stable structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a transmission electron microscopy image of the 1D cylindrical seed micelle of Example 1 of the present invention;

[0052] Figure 2 This is a transmission electron microscope image of the 2D co-assembly P1 of Example 1 of the present invention;

[0053] Figure 3 This is a transmission electron microscopy image of the 2D co-micelle P2 of Example 1 of the present invention;

[0054] Figure 4 This is a transmission electron microscopy image of the 2D co-micelle P3 of Example 1 of the present invention.

[0055] Figure 5 This is a fluorescence change diagram of the 2D co-assembly P1 after ultraviolet illumination according to Example 2 of the present invention.

[0056] Figure 6This is a fluorescence change diagram of the 2D co-assembly P1 after visible light illumination according to Example 2 of the present invention.

[0057] Figure 7 This is a graph showing the fluorescence changes of the 2D co-micelle P2 of Example 2 of the present invention after ultraviolet irradiation.

[0058] Figure 8 This is a fluorescence change diagram of the 2D co-assembly P2 after visible light illumination according to Example 2 of the present invention.

[0059] Fig. 9 This is a graph showing the fluorescence changes of the 2D co-micelle P3 of Example 2 of the present invention after ultraviolet irradiation.

[0060] Fig.10 This is a graph showing the fluorescence changes of the 2D co-micelle P3 of Example 2 of the present invention after being irradiated with visible light. DETAILED DESCRIPTION

[0061] The technical solution of the present invention is further described in detail below through specific embodiments.

[0062] The preparation method of the 2D fluorescent lamellar micelles of the present invention comprises the following steps:

[0063] (1) Synthesis of block copolymer PCL-b-PDMA;

[0064] Macromolecular initiator PCL-CTA, azobisisobutyronitrile AIBN and N,N-dimethylformamide DMA, and ultra-dry 1,4-dioxane were added to the reaction bottle. After multiple cycles of freezing, vacuuming, nitrogen filling, thawing and ventilation, the reaction bottle was placed in a 70°C oil bath for reaction for 24 hours. After the reaction was completed, it was placed in liquid nitrogen to terminate the reaction, and the block copolymer PCL-b-PDMA was obtained by centrifugation three times with n-hexane precipitation.

[0065] (2) Synthesis of homopolymer PCL-SP and homopolymer PCL-FL;

[0066] Homopolymer PCL-CTA, carboxyl spiropyran SP, 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI, 4-dimethylaminopyridine DMAP, and ultra-dry dichloromethane were added to a reaction bottle, stirred at room temperature for 3 days, and then precipitated with methanol and centrifuged three times to obtain homopolymer PCL-SP;

[0067] Homopolymer PCL-CTA, carboxyrhodamine FL, 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI, 4-dimethylaminopyridine DMAP, and ultra-dry dichloromethane were added to a reaction bottle, stirred at room temperature for 3 days, and then precipitated with methanol and centrifuged three times to obtain homopolymer PCL-FL.

[0068] (3) Preparation of 1D seed micelles;

[0069] The block copolymer PCL-b-PDMA was dissolved in anhydrous ethanol, and then slowly cooled to room temperature after heating and aged to obtain a polydisperse 1D cylindrical micelle solution; the micelle solution was ultrasonically treated in an ice water bath to obtain a monodisperse 1D cylindrical seed micelle solution;

[0070] (4) Preparation of 2D multilayer fluorescent micelles;

[0071] a. Preparation of co-assembled P1;

[0072] The 1D cylindrical seed micelle solution was diluted to a certain concentration, and PCL-SP / PCL-FL / PCL-b-PDMA monomers mixed with PCL-SP, PCL-FL and PCL-b-PDMA were dissolved in a good solvent and added dropwise to the seed micelle solution at room temperature to obtain 2D single-layer hexagonal micelles P1 in which PCL-SP / PCL-FL / PCL-b-PDMA monomers were epitaxially grown along PCL-b-PDMA short crystals;

[0073] b. Preparation of co-micelle P2;

[0074] The 1D cylindrical seed micelle solution was diluted to a certain concentration, and PCL / PCL-FL / PCL-b-PDMA monomers mixed with PCL, PCL-FL and PCL-b-PDMA were dissolved in a good solvent and added dropwise to the seed micelle solution at room temperature to obtain 2D monolayer hexagonal lamellar micelles. PCL-SP / PCL-b-PDMA monomers mixed with PCL-SP and PCL-b-PDMA were dissolved in a good solvent and added dropwise to the 2D monolayer hexagonal lamellar micelles at room temperature to obtain 2D two-layer hexagonal lamellar micelles P2.

[0075] c. Preparation of co-micelle P3;

[0076] The 1D cylindrical seed micelle solution was diluted to a certain concentration, and PCL-SP and PCL-b-PDMA monomers were dissolved in a good solvent and added dropwise to the seed micelle solution at room temperature to obtain 2D monolayer hexagonal lamellar micelles. PCL / PCL-FL / PCL-b-PDMA mixed monomers, which were a mixture of PCL, PCL-FL and PCL-b-PDMA, were dissolved in a good solvent and added dropwise to the 2D monolayer hexagonal lamellar micelles at room temperature to obtain 2D two-layer hexagonal lamellar micelles P3.

[0077] Among them, the structural formula of the block copolymer PCL-b-PDMA is:

[0078]

[0079] Wherein, X is an integer between 40 and 60, and Y is an integer between 100 and 300. Preferably, X is 50, and Y is 247.

[0080] The synthesis process of the block copolymer PCL-b-PDMA includes:

[0081] Small molecule initiators 4-(hydroxymethyl) dodecyl benzyl carbonate, caprolactone, diphenyl phosphate, and toluene were added to the reaction bottle in sequence, stirred at room temperature, precipitated and centrifuged three times in iced methanol, and vacuum dried to obtain the macromolecular initiator PCL-CTA;

[0082] The RAFT polymerization macromolecular initiator PCL-CTA, azobisisobutyronitrile, 1,4-dioxane, and N,N-dimethylacrylamide were added to the reaction bottle in sequence, and after multiple cycles of liquid nitrogen freezing-vacuuming-nitrogen-vacuuming-thawing, the reaction was placed in an oil bath under a nitrogen atmosphere; after the reaction was terminated by rapid cooling with liquid nitrogen, the block copolymer PCL-b-PDMA was obtained by precipitation and centrifugation three times in iced n-hexane and vacuum drying;

[0083] The molar ratio of the macromolecular initiator PCL-CTA, N,N-dimethylacrylamide and azobisisobutyronitrile is 1:(200-400):(0.1-0.3).

[0084] The structural formula of the above block copolymer PCL-SP is:

[0085]

[0086] Wherein, Z is an integer between 40 and 60; preferably, Z is 50.

[0087] The synthesis process of the homopolymer PCL-SP includes:

[0088] Small molecule initiators 4-(hydroxymethyl) dodecyl benzyl carbonate, caprolactone, diphenyl phosphate, and toluene were added to the reaction flask in sequence, stirred at room temperature, precipitated and centrifuged three times in iced methanol, and vacuum dried to obtain the macromolecular initiator PCL-CTA;

[0089] The macroinitiator PCL-CTA, carboxyl spiropyran SP, 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI, 4-dimethylaminopyridine DMAP, and ultra-dry dichloromethane were added to the reaction bottle, stirred at room temperature for 3 days, and then precipitated with methanol and centrifuged three times to obtain the homopolymer PCL-SP.

[0090] Among them, the molar ratio of the macromolecular initiator PCL-CTA, carboxyl spiropyran SP, 4-dimethylaminopyridine, and 1-ethyl-3 (3-dimethylpropylamine) carbodiimide is 1: (1-10): 1: (1-10).

[0091] The structural formula of the homopolymer PCL-FL is:

[0092]

[0093] Wherein, Z is an integer between 40 and 60. Preferably, Z is 50.

[0094] The synthesis process of the homopolymer PCL-FL includes:

[0095] Small molecule initiators 4-(hydroxymethyl) dodecyl benzyl carbonate, caprolactone, diphenyl phosphate, and toluene were added to the reaction flask in sequence, stirred at room temperature, precipitated and centrifuged three times in iced methanol, and vacuum dried to obtain the macromolecular initiator PCL-CTA;

[0096] The macroinitiator PCL-CTA, carboxyrhodamine FL, 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI, 4-dimethylaminopyridine DMAP, and ultra-dry dichloromethane were added into a reaction bottle, stirred at room temperature for 3 days, and then precipitated with methanol and centrifuged three times to obtain a homopolymer PCL-FL;

[0097] Among them, the molar ratio of the macromolecular initiator PCL-CTA, carboxyrhodamine FL, 4-dimethylaminopyridine, and 1-ethyl-3 (3-dimethylpropylamine) carbodiimide is (0.8-1):1:1:(1-10).

[0098] Embodiment 1:

[0099] The preparation method of the 2D fluorescent lamellar micelles of this embodiment comprises the following steps:

[0100] 1. Synthesis of PCL-CTA, PCL-SP, PCL-FL homopolymers and their block copolymer PCL-b-PDMA

[0101] (1) PCL-CTA macroinitiator was synthesized by ring-opening polymerization of caprolactone (ε-CL);

[0102] In a nitrogen-filled glove box, caprolactone (1.23 g, 10.8 mmol), diphenyl phosphate (42 mg, 0.18 mmol), 4-(hydroxymethyl) dodecylbenzyl carbonate (45 mg, 0.18 mmol) and toluene (10 mL) were added to the reaction bottle in sequence and stirred at room temperature for 6 hours. The solution was precipitated in ice methanol three times and collected by centrifugation to synthesize the macromolecular initiator PCL. 50 -CTA.

[0103] Homopolymer PCL-CTA (200 mg, 0.033 mmol), carboxyl spiropyran SP (63 mg, 0.165 mmol), 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI (32 mg, 0.165 mmol), 4-dimethylaminopyridine DMAP (4 mg, 0.033 mmol), and ultra-dry dichloromethane (4 mL) were added to the reaction bottle, stirred at room temperature for 3 days, and then precipitated with methanol and centrifuged three times to obtain homopolymer PCL 50 -SP. The structural formula is as follows:

[0104]

[0105] PCL 50 -CTA (50 mg, 0.03 mmol), carboxyrhodamine FL (9 mg, 0.033 mmol), 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI (31 mg, 0.165 mmol), 4-dimethylaminopyridine DMAP (4 mg, 0.033 mmol), and ultra-dry dichloromethane (4 mL) were added to the reaction bottle, stirred at room temperature for 3 days, and then precipitated with methanol and centrifuged three times to obtain homopolymer PCL. 50 -FL. The structural formula is as follows:

[0106]

[0107] (2) Add RAFT polymerization macroinitiator PCL into the reaction bottle in sequence 50 -CTA (200 mg, 0.033 mmol), azobisisobutyronitrile (1.15 mg, 0.007 mmol), N,N-dimethylacrylamide (1.19 g, 0.012 mmol), 1,4-dioxane (2 mL), after multiple cycles of liquid nitrogen freezing-vacuuming-nitrogen-vacuuming-thawing, placed in an oil bath under nitrogen atmosphere for reaction; after rapid cooling with liquid nitrogen to terminate the reaction, the mixture was precipitated and centrifuged three times in iced n-hexane, and vacuum dried to obtain the block copolymer PCL 50 -b-PDMA 247 Block copolymer PCL 50 -b-PDMA 247 The structural formula is as follows:

[0108]

[0109] 2. Preparation of 1D (i.e. one-dimensional) cylindrical seed micelle solution

[0110] The block copolymer PCL prepared above 50 -b-PDMA 247The solution was dissolved in anhydrous filtered ethanol at a concentration of 10 mg / mL, heated at 70 °C for 3 h, slowly cooled to room temperature, and aged for 3 days to obtain polydisperse 1D cylindrical micelles. The prepared 1D cylindrical micelles were then ultrasonically disrupted in an ice-water bath at 0 °C for 3 h by an ultrasonic cell crusher to obtain a monodisperse 1D circular seed micelle solution, as shown in FIG. Figure 1 As shown; wherein the mass of the seed micelle is the mass of the block copolymer dissolved in anhydrous ethanol.

[0111] 3. Preparation of 2D fluorescent micelles

[0112] a. Preparation of co-assembled P1;

[0113] PCL 50 -SP(20mg mL -1 ,17.5μL),PCL 50 -b-PDMA 247 (20mg mL -1 ,17.5μL),PCL 50 -FL(1mg mL -1 , 1.5 μL) of THF solution was mixed as a monomer solution;

[0114] PCL 50 -SP / PCL 50 -FL / PCL 50 -b-PDMA 247 Epitaxial growth of monomers on 1D cylindrical seed micelles: The 1D cylindrical seed micelle solution was diluted to a concentration of 0.035 mg / mL, and the above monomer solution (0.7 mg, 36.5 μL) was added to 1 mL of PCL 50 -b-PDMA 247 (0.035mg mL -1 ) in the seed micelle, and the seed growth was carried out to obtain the 2D monolayer fluorescent sheet-like co-micelle P1 in which the PCL-SP / PCL-FL / PCL-b-PDMA monomers were epitaxially grown along the PCL-b-PDMA short crystals, as shown in Figure 2 As shown, it is the transmission image of the co-micelle P1, with a size of 1 μm. The monolayer micelle structure can be clearly seen, both for SP dye and FL dye.

[0115] b. Preparation of co-micelle P2;

[0116] PCL 50 (20mg mL -1 ,17.5μL),PCL 50 -FL(1mg mL -1 ,1.5μL) and PCL 50-b-PDMA 247 (20mgmL -1 ,17.5μL) three THF solutions were mixed to obtain PCL 50 / PCL 50 -FL / PCL 50 -b-PDMA 247 Monomer;

[0117] PCL 50 / PCL 50 -FL / PCL 50 -b-PDMA 247 Epitaxial growth of monomers on 1D cylindrical seed micelles: The 1D cylindrical seed micelle solution was diluted to a concentration of 0.035 mg / mL, and the above monomer solution (0.7 mg, 36.5 μL) was added to 1 mL of PCL 50 -b-PDMA 247 (0.035mg mL -1 ) in seed micelles to obtain PCL 50 / PCL 50 -FL / PCL 50 -b-PDMA 247 2D monolayer fluorescent micelles with epitaxial growth of monomers along monolayer micelles;

[0118] PCL 50 -SP / PCL 50 -b-PDMA 247 Epitaxial growth of monomers on monolayer micelles: PCL 50 -SP(20mgmL -1 ,17.5μL),PCL 50 -b-PDMA 247 (20mg mL -1 , 17.5μL) of THF solution, added to the above-mentioned single-layer fluorescent flake micelle solution, gently shaken for 5 seconds, aged for 24 hours, and finally obtained the flake co-micelle P2 with the inner layer structure of FL dye and the outer layer structure of SP dye, as shown in Figure 3 As shown, it is the transmission image of P2, and it can be clearly seen that there are two layers of lamellar micelle structure, the inner layer structure is FL dye, and the outer layer structure is SP dye.

[0119] c. Preparation of co-micelle P3;

[0120] PCL 50 -SP(20mg mL -1 ,17.5μL),PCL 50 -b-PDMA 247 (20mg mL -1,17.5μL) two THF solutions were mixed to obtain PCL 50 -SP / PCL 50 -b-PDMA 247 Monomer;

[0121] PCL 50 -SP / PCL 50 -b-PDMA 247 Epitaxial growth of monomers on 1D cylindrical seed micelles: The 1D cylindrical seed micelle solution was diluted to a concentration of 0.035 mg / mL, and the above monomer solution (0.7 mg, 35 μL) was added to 1 mL of PCL 50 -b-PDMA 247 (0.035mg mL -1 ) in seed micelles to obtain PCL 50 -SP / PCL 50 -b-PDMA 247 2D monolayer fluorescent micelles with epitaxial growth of monomers along monolayer micelles;

[0122] PCL 50 / PCL 50 -FL / PCL 50 -b-PDMA 247 Epitaxial growth of monomers on monolayer micelles: PCL 50 (20mg mL -1 ,17.5μL),PCL 50 -FL(1mg mL -1 ,1.5μL) and PCL 50 -b-PDMA 247 (20mg mL -1 , 17.5 μL) of THF solution, added to the above monolayer micelle solution, gently shaken for 5 seconds, aged for 24 hours, and finally obtained the sheet co-micelle P3 with the inner layer structure of SP dye and the outer layer structure of FL dye. Figure 4 As shown, it is the transmission image of P3, and it can be clearly seen that there are two layers of lamellar micelle structure, the inner layer structure is SP dye, and the outer layer structure is FL dye.

[0123] Embodiment 2:

[0124] The fluorescence changes of the three 2D lamellar micelles P1, P2 and P3 prepared in Example 1 were detected as follows:

[0125] The prepared co-assembled P1 was irradiated with 365nm UV light for 0min, 1min, 3min, 5min, and 6min, and the fluorescence performance was tested on a fluorescence spectrometer in turn. Figure 5As shown, the results show that with the increase of illumination time, SP gradually opens its ring to form a fluorescent isomer MC, the fluorescence intensity of FL at 510 nm gradually decreases, while the fluorescence intensity of MC (the open ring isomer of SP) at 650 nm gradually increases, indicating that a FRET effect occurs between FL and MC, FL is the donor, MC is the acceptor, FL absorbs light energy and transfers energy to MC, resulting in a decrease in the fluorescence intensity of FL and an increase in the fluorescence intensity of MC.

[0126] The prepared co-assembly P1 was irradiated with visible light for 0 min, 1 min, 3 min, 5 min, 10 min, 15 min, and 20 min, and the fluorescence performance was tested on a fluorescence spectrometer in turn. Figure 6 As shown, the results show that with the increase of visible light irradiation time, MC gradually closes and transforms back to non-fluorescent SP, the fluorescence intensity of FL at 510nm gradually increases, while the fluorescence intensity of MC at 650nm gradually decreases, FL cannot produce FRET effect with SP, and with the increase of visible light irradiation time, FL fluorescence intensity increases and MC fluorescence intensity decreases, which also illustrates the dynamic reversibility of SP.

[0127] The prepared co-micelle P2 was irradiated with a 365 nm UV lamp for 0 min, 1 min, 3 min, 5 min, and 6 min, and the fluorescence properties were tested on a fluorescence spectrometer in turn. Figure 7 As shown in the figure, the results show that with the increase of illumination time, SP gradually opens the ring to form the fluorescent isomer MC. The fluorescence intensity of FL at 510nm gradually decreases, while the fluorescence intensity of MC at 650nm gradually increases, indicating that the FRET effect occurs between FL and MC. FL is the donor and MC is the acceptor. FL absorbs light energy and transfers energy to MC, resulting in a decrease in FL fluorescence intensity and an increase in MC fluorescence intensity. The FRET efficiency of the co-micelle P2 is not as high as that of the co-assembly P1, which may be due to the structure affecting the FRET efficiency.

[0128] The prepared co-micelles P2 were irradiated with visible light for 0 min, 1 min, 3 min, 5 min, 10 min, 15 min, and 20 min, and the fluorescence properties were tested on a fluorescence spectrometer in turn. Figure 8 As shown, the results show that with the increase of visible light irradiation time, MC gradually closes the ring and transforms back to non-fluorescent SP. The fluorescence intensity of FL at 510nm gradually increases, while the fluorescence intensity of MC at 650nm gradually decreases. FL cannot produce FRET effect with SP. With the increase of visible light irradiation time, the fluorescence intensity of FL increases and the fluorescence intensity of MC decreases, indicating that SP has dynamic reversibility.

[0129] The prepared co-micelle P3 was irradiated with a 365 nm UV lamp for 0 min, 1 min, 3 min, 5 min, and 6 min, and the fluorescence properties were tested on a fluorescence spectrometer in turn. Fig. 9 As shown in the figure, with the increase of illumination time, the fluorescence intensity of FL at 510nm decreases slightly, and the fluorescence intensity of MC at 650nm decreases slightly. The changes are not very obvious. There is almost no FRET effect between FL and MC. It may be the FRET effect affected by the structure. When SP is in the inner layer and FL is in the outer layer, it may be due to the limitation of the inner space that SP is difficult to convert into the isomer MC, resulting in unclear fluorescence changes.

[0130] The prepared co-micelles P3 were irradiated with visible light for 0 min, 1 min, 3 min, 5 min, 10 min, 15 min, and 20 min, and the fluorescence properties were tested on a fluorescence spectrometer in turn. Fig.10 As shown, the results show that with the increase of visible light irradiation time, a few MCs gradually closed their rings and converted back to non-fluorescent SP. The fluorescence intensity of FL at 510 nm increased slightly, while the fluorescence intensity of MC at 650 nm decreased slightly, indicating that SP has dynamic reversibility. The FRET efficiency of co-micelle P3 is the smallest, followed by co-micelle P2, and the co-assembly P1 has the largest FRET efficiency.

[0131] In view of the numerous embodiments of the scheme of the present invention, the raw materials and dosage involved can be selected according to actual needs within the limited range, and the experimental data of each embodiment is huge and numerous, which is not suitable for listing and explaining one by one here, but the content required to be verified and the final conclusion obtained in each embodiment are similar. Therefore, the verification content of each embodiment will not be explained one by one here.

[0132] The above description is only a detailed description of the preferred embodiments and principles of the present invention. For ordinary technicians in this field, according to the ideas provided by the present invention, there will be changes in the specific implementation methods, and these changes should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing 2D fluorescent lamellar micelles, characterized in that: The following steps are involved: (1) Synthesis of block copolymer PCL-b-PDMA, homopolymer PCL-SP, and homopolymer PCL-FL; Wherein, the structural formula of the block copolymer PCL-b-PDMA is: Wherein, X is an integer between 40 and 60, and Y is an integer between 100 and 300; The structural formula of the homopolymer PCL-SP is: Wherein, Z is an integer between 40 and 60; The structural formula of the homopolymer PCL-FL is: Wherein, Z is an integer between 40 and 60; (2) Preparation of 1D seed micelles; The block copolymer PCL-b-PDMA was dissolved in anhydrous ethanol, and after heating treatment, cooled to room temperature and aged to obtain a polydisperse 1D cylindrical micelle solution, which was then ultrasonically treated in an ice-water bath to obtain a monodisperse 1D cylindrical seed micelle solution; (3) Preparation of 2D fluorescent lamellar micelles; Based on the block copolymer PCL-b-PDMA, homopolymer PCL-SP, and homopolymer PCL-FL, 2D single-layer fluorescent lamellar micelles or 2D two-layer fluorescent lamellar micelles are generated in the seed micelle solution obtained in step (2).

2. The preparation method according to claim 1, characterized in that: The step (3) specifically comprises: A PCL-SP / PCL-FL / PCL-b-PDMA monomer mixed with homopolymer PCL-SP, homopolymer PCL-FL and block copolymer PCL-b-PDMA is dissolved in a good solvent and then added dropwise to the seed micelle solution obtained in step (2) to obtain a 2D monolayer lamellar micelle in which the PCL-SP / PCL-FL / PCL-b-PDMA monomer is epitaxially grown along the PCL-b-PDMA short crystals.

3. The preparation method according to claim 2, characterized in that: The mass ratio of the homopolymer PCL-SP, the homopolymer PCL-FL and the block copolymer PCL-b-PDMA is 1:(0.003-0.006):1; The mass ratio of PCL-SP / PCL-FL / PCL-b-PDMA monomer to the seed micelle in the seed micelle solution is (1-30):1; The good solvent is one or more of tetrahydrofuran, chloroform, dimethylformamide, 1,4-dioxane, and dimethyl sulfoxide.

4. The preparation method according to claim 1, characterized in that: The step (3) specifically comprises: Dissolving PCL / PCL-FL / PCL-b-PDMA monomers mixed with PCL, homopolymer PCL-FL and block copolymer PCL-b-PDMA in a good solvent, and then dropping the monomers into the seed micelle solution obtained in step (2) to obtain a 2D monolayer micelle solution; Then, the PCL-SP / PCL-b-PDMA monomer, which is a mixture of the homopolymer PCL-SP and the block copolymer PCL-b-PDMA, is dissolved in a good solvent and then added dropwise to the 2D monolayer lamellar micelle solution to obtain 2D two-layer lamellar micelles.

5. The preparation method according to claim 1, characterized in that: The step (3) specifically comprises: Dissolving a PCL-SP / PCL-b-PDMA monomer obtained by mixing a homopolymer PCL-SP and a block copolymer PCL-b-PDMA in a good solvent, and then dropping the monomer into the seed micelle solution obtained in step (2) to obtain a 2D monolayer micelle solution; Then, PCL / PCL-FL / PCL-b-PDMA monomers, which are a mixture of PCL, homopolymer PCL-FL and block copolymer PCL-b-PDMA, are dissolved in a good solvent and then added dropwise to the 2D monolayer lamellar micelle solution to obtain 2D two-layer lamellar micelles.

6. The preparation method according to claim 4 or 5, characterized in that: The mass ratio of PCL, homopolymer PCL-FL and block copolymer PCL-b-PDMA in the PCL / PCL-FL / PCL-b-PDMA monomer is 1:(0.003-0.006):1; The mass ratio of homopolymer PCL-SP and block copolymer PCL-b-PDMA in PCL-SP / PCL-b-PDMA monomer is 1:(0.2-5); The mass ratio of PCL-SP / PCL-b-PDMA monomer or PCL / PCL-FL / PCL-b-PDMA monomer to the seed micelle in the seed micelle solution is (1-30):1; The good solvent is one or more of tetrahydrofuran, chloroform, dimethylformamide, 1,4-dioxane, and dimethyl sulfoxide.

7. The preparation method according to any one of claims 1 to 5, characterized in that: The synthesis of the block copolymer PCL-b-PDMA comprises: Small molecule initiators 4-(hydroxymethyl) dodecyl benzyl carbonate, caprolactone, diphenyl phosphate, and toluene were added to the reaction bottle in sequence, stirred at room temperature, precipitated and centrifuged several times in iced methanol, and vacuum dried to obtain the macromolecular initiator PCL-CTA; The RAFT polymerization macromolecular initiator PCL-CTA, azobisisobutyronitrile, 1,4-dioxane, and N,N-dimethylacrylamide were added to the reaction bottle in sequence, and after multiple cycles of liquid nitrogen freezing-vacuuming-nitrogen-vacuuming-thawing, the reaction was placed in an oil bath under a nitrogen atmosphere; after the reaction was terminated by rapid cooling with liquid nitrogen, the block copolymer PCL-b-PDMA was obtained by precipitation and centrifugation in iced n-hexane for several times and vacuum drying; The molar ratio of the macromolecular initiator PCL-CTA, N,N-dimethylacrylamide and azobisisobutyronitrile is 1:(200-400):(0.1-0.3).

8. The preparation method according to any one of claims 1 to 5, characterized in that: The synthesis of the homopolymer PCL-SP comprises: Small molecule initiators 4-(hydroxymethyl) dodecyl benzyl carbonate, caprolactone, diphenyl phosphate, and toluene were added to the reaction flask in sequence, stirred at room temperature, precipitated and centrifuged several times in iced methanol, and vacuum dried to obtain the macromolecular initiator PCL-CTA; The macroinitiator PCL-CTA, carboxyl spiropyran SP, 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI, 4-dimethylaminopyridine DMAP, and ultra-dry dichloromethane were added into a reaction bottle, stirred at room temperature for several days, and then precipitated with methanol and centrifuged several times to obtain the homopolymer PCL-SP; Among them, the molar ratio of the macromolecular initiator PCL-CTA, carboxyl spiropyran SP, 4-dimethylaminopyridine DMAP, and 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI is 1: (1-10): 1: (1-10).

9. The preparation method according to any one of claims 1 to 5, characterized in that: The synthesis of the homopolymer PCL-FL comprises: Small molecule initiators 4-(hydroxymethyl) dodecyl benzyl carbonate, caprolactone, diphenyl phosphate, and toluene were added to the reaction flask in sequence, stirred at room temperature, precipitated and centrifuged several times in iced methanol, and vacuum dried to obtain the macromolecular initiator PCL-CTA; The macroinitiator PCL-CTA, carboxyl rhodamine FL, 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI, 4-dimethylaminopyridine DMAP, and ultra-dry dichloromethane were added to a reaction bottle, stirred at room temperature for 3 days, and then precipitated with methanol and centrifuged three times to obtain a homopolymer PCL-FL; Among them, the molar ratio of the macromolecular initiator PCL-CTA, carboxyrhodamine FL, 4-dimethylaminopyridine DMAP, and 1-ethyl-3 (3-dimethylpropylamine) carbodiimide EDCI is (0.8-1):1:1:(1-10).

10. The 2D fluorescent lamellar micelles prepared by the preparation method according to any one of claims 1 to 9.

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