Flower-shaped giant polymer vesicle and its preparation method and application

Abstract

The present invention belongs to the field of polymer materials, and relates to a giant polymer vesicle with a flower-like structure, and a preparation method and application thereof. The giant polymer vesicle with a flower-like structure is mainly prepared by self-assembly of an amphiphilic block copolymer; or prepared by self-assembly of an amphiphilic block copolymer and a hydrophobic polymer; the shell of the giant polymer vesicle with a flower-like structure has a hollow membrane structure similar to a petal and a solid central spherical core structure; wherein the inner and outer layers of the petal-like hollow membrane structure are composed of hydrophilic segments or hydrophobic polymers in the amphiphilic block copolymer; the central spherical core is composed of polymer vesicle aggregation and extrusion; the giant polymer vesicle with a flower-like structure of the present invention can be used in the fields related to efficient nanocarriers, controlled drug release and nanoreactors, and can effectively load multiple types of drug molecules on a single platform to achieve the effect of simultaneous delivery of multiple drug molecules.

Description

Technical Field

[0001] The invention belongs to the field of polymer materials and relates to a giant polymer vesicle with a flower-like structure and a preparation method and application thereof. Technical Background

[0002] In the past few decades, the controlled self-assembly of amphiphilic block copolymers that mimics nature has attracted considerable research interest from researchers. As we all know, block copolymers are a special class of polymers formed by covalently linking two or more polymer segments with distinct physical and chemical properties. Since the incompatible blocks are linked by covalent bonds, block copolymers undergo microphase separation under specific conditions, and thus a variety of ordered nanostructures (including spherical, cylindrical, lamellar, vesicles, virus-like vesicles, etc.) can be obtained. Block copolymer self-assembly refers to a method in which block copolymers spontaneously transform from disorder to order to form regular structures under specific conditions. Studies have found that the morphology of the assembly can be regulated by many factors, including polymer composition, polymer concentration, solvent properties, water content, etc. And assemblies with different morphologies have different application values ​​in the fields of drug delivery, sustained and controlled release, bioimaging, and stimulus-responsive sensors.

[0003] Since the structural morphology is closely related to the performance and application of the assembly, exploring the preparation methods of amphiphilic block copolymer assemblies with new morphologies through different methods remains one of the research goals in the field of polymer materials. At present, there are no public reports on flower-like giant vesicles. Summary of the invention

[0004] Based on the basic morphology and characteristics of flowers in nature, the purpose of the present invention is to provide a polymer vesicle with a flower-like structure.

[0005] Another object of the present invention is to provide a preparation method for the formation process of the above-mentioned flower-like structure giant polymer vesicles.

[0006] Another object of the present invention is to provide a method for preparing the above-mentioned giant polymer vesicles with flower-like structure.

[0007] Another object of the present invention is to provide applications of the above-mentioned giant polymer vesicles with flower-like structure.

[0008] The purpose of the present invention is achieved through the following technical solutions:

[0009] A giant polymer vesicle with a flower-like structure, which is mainly prepared by self-assembly of an amphiphilic block copolymer; or prepared by self-assembly of an amphiphilic block copolymer and a hydrophobic polymer; the shell of the giant polymer vesicle with a flower-like structure has a petal-like hollow membrane structure and a solid central spherical core structure; wherein the inner and outer layers of the petal-like hollow membrane structure are composed of hydrophilic segments or hydrophobic polymers in the amphiphilic block copolymer; and the central spherical core is composed of aggregated extrusion of polymer vesicles;

[0010] The molecular weight n of the hydrophilic segment in the amphiphilic block copolymer is ≥1000Da, preferably 1000-10000Da; the molecular weight m of the hydrophobic segment in the amphiphilic block copolymer is ≥2000Da, preferably 2000Da-100000Da.

[0011] The diameter of the flower-like giant polymer vesicle is 1 μm to 20 μm, preferably 10 μm.

[0012] The hydrophilic segment in the amphiphilic block copolymer is at least one of polyethylene glycol and poly (2-methacrylate ethoxyphosphocholine), and the hydrophobic segment in the amphiphilic block copolymer is one of polystyrene, polylactic acid, polycaprolactone, and poly (2-diisopropylaminoethyl methacrylate); preferably, the amphiphilic front-end copolymer is a PEGn-b-PSm copolymer.

[0013] The hydrophobic polymer is a saturated fatty acid, including at least one of stearic acid, lauric acid, palmitic acid, caprylic acid, capric acid, myristic acid, palmitic acid, and arachidic acid; preferably, it is a mixture of stearic acid and lauric acid, and the mass ratio of stearic acid to lauric acid is 1 to 10:1 to 5, preferably 4:1.

[0014] When the flower-like giant polymer vesicles are prepared by self-assembly of an amphiphilic block copolymer and a hydrophobic polymer, the mass ratio of the amphiphilic block copolymer to the hydrophobic polymer is 0.5 to 2; the molecular weight ratio of the amphiphilic block copolymer to the hydrophobic polymer is 1:(30 to 80);

[0015] The flower-like giant polymer vesicle also includes a load, which is at least one of a drug, an antibody, a protein, a gene fragment, a fluorescent molecule and a growth factor;

[0016] The drug is preferably doxorubicin (DOX); the antibody is preferably at least one of immunoglobulin G, panitumumab (Vectibix) and T-DM1 (Kadcyla); the protein is preferably bovine serum albumin (BSA); and the fluorescent molecule is at least one of Nile red, rhodamine and fluorescein isothiocyanate (FITC).

[0017] A method for preparing giant polymer vesicles with a flower-like structure, comprising the following steps:

[0018] (1) Preparation of polymer solution: adding an amphiphilic block copolymer or a mixture of an amphiphilic block copolymer and a hydrophobic polymer into an organic solvent, stirring and mixing, to obtain a polymer solution;

[0019] (2) Treatment of polymer solution: The polymer solution is quenched by adding water at different temperatures to obtain flower-shaped giant polymer vesicles.

[0020] The organic solvent in step (1) is at least one of tetrahydrofuran (THF), 1,4-dioxane, N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAC), dichloromethane (DCM), chloroform (CHCl3), methylacetate, acetonitrile, ethanol, methyl isobutyl ketone (MIBK), hexafluoroisopropanol (HFIP), acetone and petroleum ether. Preferably, tetrahydrofuran and 1,4-dioxane are used, and the volume ratio of the mixture of tetrahydrofuran and 1,4-dioxane is 1 to 10:1 to 5, and the preferred ratio is 3:2.

[0021] The mass volume ratio of the amphiphilic block copolymer or the mixture of the amphiphilic block copolymer and the hydrophobic polymer to the organic solvent is 1-50 mg:0.5-5 mL; preferably 10 mg:1 mL.

[0022] The stirring rate during mixing and stirring in step (1) is 100 to 1500 rpm.

[0023] The specific steps of quenching the polymer solution and ultrapure water at different temperatures in step (2) are as follows:

[0024] First, water with a temperature of 40 to 60° C. is injected into a polymer solution to obtain a fusion polymer vesicle solution, and then the obtained fusion polymer vesicle solution is added into water with a temperature of 10 to 25° C. to obtain giant polymer vesicles with a flower-like structure.

[0025] The volume ratio of water to polymer solution is 2 to 5:1, preferably 3 to 1. The injection rate of water is preferably 0.1 to 5 mL / h, preferably 1 mL / h. The stirring rate is 200 to 1500 rpm, preferably 700 rpm.

[0026] The volume ratio of the second fusogenic polymer vesicle solution to water is 1-10:10-100, preferably 2:15.

[0027] The giant flower-like polymer vesicles obtained in step (2) are mixed with a load and water to obtain giant flower-like polymer vesicles loaded with the load, wherein the water can also be replaced by a PBS buffer solution or other similar solvent commonly used in the art.

[0028] A giant polymer vesicle with a flower-like structure is used in the fields of high-efficiency nanocarriers, controlled drug release and nanoreactors.

[0029] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0030] (1) The preparation process of the present invention is simple and feasible, with high production efficiency and good repeatability, and is suitable for the promotion of the preparation method of giant polymer vesicles with flower-like structure;

[0031] (2) The giant polymer vesicles with flower-like structures of the present invention can be used in the fields of high-efficiency nanocarriers, drug controlled release and nanoreactors, and can effectively load multiple types of drug molecules on a single platform to achieve the effect of simultaneous delivery of multiple drug molecules. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The intermediate transition state transmission and scanning electron microscope photos of the giant polymer vesicle with flower-like structure prepared in Example 1 are taken at a magnification of 60,000 times;

[0033] Figure 2 This is a scanning electron microscope photo of the intermediate transition state of the flower-like giant polymer vesicle prepared in Example 1, with a magnification of 43,000 times

[0034] Figure 3 This is a transmission electron microscope photo of the giant polymer vesicle with flower-like structure prepared in Example 2, with a magnification of 25,000 times;

[0035] Figure 4 This is a transmission electron microscope photo of the giant polymer vesicle with flower-like structure prepared in Example 2, with a magnification of 30,000 times;

[0036] Figure 5 These are confocal microscopy images of the flower-like giant polymer vesicles loaded with DOX prepared in Example 2 3 hours after being engulfed by cells; (1) is a confocal microscopy image of FITC, (2) is a confocal microscopy image of DOX, (3) is a laser confocal microscopy image of cell nucleus staining, and (4) is a merged image of (1) to (3). DETAILED DESCRIPTION

[0037] The present invention is further explained below with reference to the following examples, but the examples do not limit the present invention in any form.

[0038] Example 1

[0039] Take 10mg PEGn-b-PSm and dissolve it in 1mL of a mixed solution of tetrahydrofuran and dipentane with a volume ratio of 3:2, and continue stirring at a rate of 300rpm using a magnetic stirrer until it is completely dissolved. Then add 5mg of stearic acid and lauric acid with a mass ratio of 4:1. Continue stirring at a stirring rate of 500rpm until it is completely dissolved. Then adjust the stirring rate to 700rpm, and add 3mL of ultrapure water at an injection rate of 1mL / h at 45°C through a microinjection pump. After the injection is completed, the intermediate transition state morphology of the preparation of flower-shaped giant polymer vesicles is obtained.

[0040] Example 2

[0041] Take 10 mg of PEGn-b-PSm and dissolve it in 1 mL of a mixed solution of tetrahydrofuran and dipentane in a volume ratio of 3:2. Use a magnetic stirrer (stirring speed is 300 rpm) to continue stirring until completely dissolved. Then add 5 mg of stearic acid and lauric acid in a mass ratio of 4:1. Continue stirring at a stirring rate of 500 rpm until completely dissolved. Then adjust the stirring rate to 700 rpm, and add 3 mL of ultrapure water at an injection rate of 1 mL / h at 45°C through a microinjection pump. After the injection is completed, use a pipette to draw 200 μL of the milky white solution, and then quickly add it to 1.5 mL of ultrapure water at 20°C at one time to obtain flower-shaped giant polymer vesicles. Figure 3 and Figure 4 As shown, the shell of the flower-like giant polymer vesicle has a petal-like hollow membrane structure and a solid central spherical core structure.

[0042] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A method for preparing giant polymer vesicles with flower-like structure, characterized in that Here are the steps: (1) Preparation of polymer solution: adding a mixture of an amphiphilic block copolymer and a hydrophobic polymer into an organic solvent, stirring and mixing, to obtain a polymer solution; (2) Treatment of polymer solution: adding the polymer solution to water at different temperatures in a quenching manner to obtain flower-shaped giant polymer vesicles, adding a load and water or PBS buffer solution to obtain flower-shaped giant polymer vesicles loaded with the load; In step (1), the amphiphilic block copolymer is a PEGn-b-PSm copolymer; the hydrophobic polymer is a mixture of stearic acid and lauric acid; The organic solvent in step (1) is a mixed solution of tetrahydrofuran and dipentane; The specific steps of quenching the polymer solution and ultrapure water at different temperatures in step (2) are as follows: First, water at a temperature of 40 to 60° C. is injected into a polymer solution to obtain a fusion polymer vesicle solution, and then the obtained fusion polymer vesicle solution is added into water at a temperature of 10 to 25° C. to obtain a giant polymer vesicle with a flower-like structure; The giant polymer vesicle with flower-like structure is prepared by self-assembly of amphiphilic block copolymer and hydrophobic polymer; the shell of the giant polymer vesicle with flower-like structure has a petal-like hollow membrane structure and a solid central spherical core structure; the inner and outer layers of the petal-like hollow membrane structure are composed of hydrophilic segments or hydrophobic polymers in the amphiphilic block copolymer; the central spherical core is composed of polymer vesicle aggregation and extrusion; The molecular weight of the hydrophilic segment in the amphiphilic block copolymer is ≥1000Da; the molecular weight of the hydrophobic segment in the amphiphilic block copolymer is ≥2000Da.

2. The method for preparing giant polymer vesicles with flower-like structure according to claim 1, characterized in that: The mass ratio of the amphiphilic block copolymer to the hydrophobic polymer is 0.5-2; the molecular weight ratio of the amphiphilic block copolymer to the hydrophobic polymer is 1:(30-80).

3. The method for preparing giant polymer vesicles with flower-like structure according to claim 1, characterized in that: The size of the flower-like giant polymer vesicles is 1 μm to 20 μm; The flower-like giant polymer vesicle also includes a load, which is at least one of a drug, an antibody, a protein, a gene fragment, a fluorescent molecule and a growth factor.

4. The method for preparing giant polymer vesicles with flower-like structure according to claim 1, characterized in that: The mass volume ratio of the amphiphilic block copolymer or the mixture of the amphiphilic block copolymer and the hydrophobic polymer to the organic solvent is 1-50 mg: 0.5-5 mL.

5. The method for preparing flower-like giant polymer vesicles according to claim 1, characterized in that: The method first injects water with a temperature of 40-60°C into the polymer solution, wherein the volume ratio of water to the polymer solution is 2-5:1; and then adds the obtained fusion polymer vesicle solution into water with a temperature of 10-25°C, wherein the volume ratio of the fusion polymer vesicle solution to water is 1-10:10-100.

6. The method for preparing flower-like giant polymer vesicles according to claim 1, characterized in that: When the water is injected into the polymer solution, the injection rate of the water is 0.1-5 mL / h; The giant polymer vesicles with flower-like structure obtained in step (2) are mixed with a load and water to obtain giant polymer vesicles with flower-like structure loaded with the load.

7. Application of the giant polymer vesicles with flower-like structure prepared by the method according to any one of claims 1 to 6 in the fields of efficient nanocarriers, drug controlled release and nanoreactors.

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