Injectable hydrogel with active oxygen response capability as well as preparation method and application of injectable hydrogel

Abstract

The invention belongs to the technical field of injectable hydrogel preparation, and particularly relates to injectable hydrogel with active oxygen response capacity and a preparation method and application thereof. The preparation method comprises the following steps: firstly, synthesizing an ABA type amphiphilic triblock polymer with active oxygen response capability, and obtaining the hydrogel through a solution self-assembly method. The strength of the hydrogel is 1Pa-1MPa, the hydrogel can load hydrophilic and hydrophobic drugs, has injectability and an in-vivo active oxygen response function, selectively and intelligently releases the drugs in a controlled manner according to different in-vivo active oxygen concentrations of 10-1000 [mu] M, has active oxygen concentration adaptability, and can be decomposed within 3-20 days. And intelligent and accurate on-demand delivery and release of the medicine are realized. The gel has the advantages of high biocompatibility, biomedical safety and degradability.

Description

Technical Field

[0001] The invention belongs to the technical field of injectable hydrogel preparation, and specifically relates to an injectable hydrogel with active oxygen responsiveness, a preparation method and application thereof. The injectable hydrogel can be used as an intelligent drug delivery carrier. Background Art

[0002] Advanced drug delivery systems are of great significance for the precise treatment of diseases and the rapid recovery of patients. Common drug delivery systems include oral, intravenous, and transdermal injections, which achieve precise drug delivery and disease treatment. Commonly used oral drugs or intravenous injection methods must pass through multiple biological barriers, which limits their therapeutic effects. Large doses or repeated administration often lead to drug off-target and unnecessary toxic side effects. Therefore, local treatment at the site of the disease and controlled release of drugs can improve the efficiency of treatment, but traditional in vivo injections of drugs are dispersed in body fluids after the drugs are injected into the body, and are quickly dispersed with the blood circulation, making it difficult to achieve precise treatment and controlled release of drugs. Injectable hydrogel drug carriers can avoid the problem of short-term diffusion of drugs. When the injectable hydrogel with drugs is injected into the disease site, a gel domain rich in high-concentration drugs is formed, which will not disperse with the body fluid environment, reducing the in vivo toxic side effects caused by uncontrollable diffusion ( Adv. Drug Deliver. Rev. 2021, 171, 240.).

[0003] Dutch scientists Meijer and others introduced quadruple hydrogen bonding units at both ends of the polyethylene oxide molecular chain, obtained a fibrous assembly through a self-assembly method, and formed a gel, which can be used as an injectable drug carrier. However, this molecular structure does not have responsive properties and it is difficult to achieve effective drug release in vivo ( Adv. Mater. 2012, 24, 2703). In addition, Chinese scientists Wang et al. used polypeptide chains to combine hydrophobic molecules to form amphiphilic molecules, and formed nanofiber assemblies by controlling the assembly environment to prepare injectable hydrogels, which can be loaded with drugs of different properties and achieve gelation injection in vivo. However, the cost of designing amphiphilic assemblies through polypeptide molecules is high, it is difficult to achieve precise synthesis of molecular structures, and it does not have intelligent response characteristics ( Nano Lett. 2022, 22 , 4182.).

[0004] Through modular synthesis methods (such as esterification reaction, "click chemistry", etc.), molecules of different compositions can be synthesized into block-structured macromolecules, achieving the synthesis of precise macromolecules ( Polymer 2017, 125 , 303.). In addition, multi-block structure molecules can be assembled into different microphase structures according to different environments, achieving bottom-up control of the macroscopic physical properties of the material ( Prog. Polym. Sci.2020, 103 , 101230).

[0005] In order to overcome the technical problems existing in the existing technology and better achieve precise drug delivery and disease treatment, it is urgent to develop a more effective drug delivery system. Summary of the invention

[0006] The purpose of the present invention is to provide an injectable hydrogel with reactive oxygen species (ROS) responsiveness, and a preparation method and application thereof. The hydrogel prepared by the present invention has excellent biocompatibility and biodegradability, can effectively load various hydrophilic and hydrophobic drug molecules, and adaptively release drugs according to the level of reactive oxygen molecules in the body.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows: The injectable hydrogel with ROS responsiveness described in the present invention is an ABA-type amphiphilic triblock polymer with ROS responsive functional groups, which is self-assembled from a solution to form an injectable hydrogel loaded with drugs; In the ABA type amphiphilic triblock polymer, A is a hydrophobic block molecule, B is a hydrophilic block molecule, and the ROS responsive functional group is connected between the hydrophobic block molecules. Specifically, the ROS responsive functional group can be connected between the A block and the B block, i.e., A-ROS-B-ROS-A, or can be connected in the middle of the B block, i.e., AB-ROS-BA. The ROS responsive functional group can be broken in the presence of ROS and decomposed into segment molecules ( Figure 1 ).

[0008] The method for preparing the injectable hydrogel with ROS responsiveness of the present invention comprises the following steps: (1) The hydrophobic block molecules, hydrophilic block molecules and ROS-responsive functional groups are subjected to esterification reaction, amidation reaction and "click chemistry" reaction to obtain an ABA-type amphiphilic triblock polymer with ROS-responsive ability; (2) The injectable hydrogel is constructed by a solution self-assembly method using an ABA-type amphiphilic triblock polymer, and drug molecules are loaded simultaneously during the hydrogel assembly process.

[0009] The specific operation of the solution self-assembly is as follows: a. dissolving an ABA type amphiphilic triblock polymer in an organic solvent to obtain an ABA solution; b. Add water to the ABA solution to induce polymer self-assembly to obtain a hydrogel, and perform dialysis to remove the organic solvent to obtain the injectable hydrogel.

[0010] The drug molecules include hydrophobic drugs and hydrophilic drugs. The specific operation of drug molecule loading is as follows: the hydrophobic drug and the ABA-type amphiphilic triblock polymer are dissolved in an organic solvent; the hydrophilic drug is dissolved in the water described in step b, and an injectable hydrogel loaded with drug molecules can be obtained; the loading amount of the hydrophobic drug and the hydrophilic drug is 0.01wt.%-20wt.% of the mass of the ABA-type amphiphilic triblock polymer.

[0011] Preferably, the hydrophobic block molecules include polypolyhedral silsesquioxane, polymethyl methacrylate, polyethyl acrylate, polydimethylsiloxane, polylactic acid, polystyrene, polycaprolactone or polylactide; the mass of the hydrophobic block molecules is 5wt.%-50wt.% of the ABA type amphiphilic triblock polymer.

[0012] Preferably, the hydrophilic block molecule includes polyethylene oxide, polyvinyl pyrrolidone, polyacrylamide, polyvinyl alcohol, polytetrahydrofuran, polyethylene imine, poly(2-ethyl-2-oxazoline), polyvinyl pyridine or polyacrylic acid; and the number average molecular weight of the hydrophilic block molecule is 100 g / mol-1000000 g / mol.

[0013] Preferably, the ROS responsive functional groups include ketone thioether (thioacetone bond), phenyl borate ester, selenium-selenium bond, tellurium-tellurium bond, thioether bond, and trithioester bond.

[0014] Preferably, the organic solvent includes N, N-dimethylformamide, dimethyl sulfoxide, 1,4-dioxane or tetrahydrofuran.

[0015] Preferably, in the ABA solution, the concentration of the ABA type amphiphilic triblock polymer is 0.01wt.%-50wt.%; Preferably, the volume ratio of water added in step b to ABA solution is 10:1-1:10, wherein the water is high-purity water or physiological saline. When adding water to the ABA solution, it is necessary to stir or shake and drip slowly, and the dripping rate of water is 0.01 μL / min-1 mL / min.

[0016] Preferably, the dialysis method is to add pure water or physiological saline to the hydrogel, change the water every 10-12 hours, and dialyze for 3-4 days.

[0017] As a preferred technical solution: the hydrophobic block molecule is polypolyhedral silsesquioxane, the hydrophilic block molecule is polyethylene oxide, the ROS responsive functional group is ketone thioether, and the synthesis route is as follows: Figure 3 , Figure 4 , Figure 5As shown, the final ABA-type amphiphilic triblock polymer is obtained. The obtained ABA-type amphiphilic triblock polymer and hydrophobic drugs are added to the solvent tetrahydrofuran, the concentration of the ABA-type amphiphilic triblock polymer is 10wt.%, and then the aqueous solution containing the hydrophilic drug is slowly dripped into the ABA solution, the dripping rate is 5μL / min, and the volume ratio of the aqueous solution to the ABA solution is 4:1 to obtain a gel. During the preparation of the gel, the drug loading of the hydrophobic drug and the hydrophilic drug molecules is 1wt.% of the mass of the ABA-type amphiphilic triblock polymer, respectively. The obtained gel material is immersed in water, and the tetrahydrofuran solvent is removed by dialyzing. The mechanical deformation force of the hydrogel is 600Pa ( Figure 6 ), which is injectable and starts to decompose on the third day at a reactive oxygen molecule concentration of 200 μM.

[0018] The injectable hydrogel with ROS responsiveness described in the present invention is used as a drug delivery system to load hydrophilic drugs and / or hydrophobic drugs, is injectable, and is in a hydrogel state before and after injection, achieving adaptive drug release in vivo based on tissue ROS levels.

[0019] The mechanism of the present invention is as follows: Through molecular design and synthesis methods, an amphiphilic block polymer with ROS responsiveness is obtained. The hydrophobic block molecules, hydrophilic block molecules and ROS responsive functional groups are esterified, amidated and "click-chemistry" to obtain an ABA-type amphiphilic triblock polymer with ROS responsiveness. The ROS responsive functional groups are connected between the hydrophobic block molecules. The ROS responsive functional groups can be broken in the presence of ROS and decomposed into segment molecules ( Figure 1 ). The ABA-type amphiphilic triblock polymer is used to construct an injectable hydrogel through a solution assembly method. During the hydrogel assembly process, the drug molecules are loaded simultaneously. First, the ABA-type amphiphilic triblock polymer and the hydrophobic drug are dissolved in a good solvent of the ABA-type amphiphilic triblock polymer and the hydrophobic drug to obtain a solution, and then the aqueous solution containing the hydrophilic drug is slowly dripped into the solution. As the water content in the solution increases, the polarity of the solution changes, the solubility of the A block decreases, and it gradually assembles together to form a hydrophobic region, forming a spherical phase or a nanofiber-like periscopic structure by self-assembly. Figure 1 Transmission electron microscope image). Block B has good solubility and acts as a bridge molecule to connect the hydrophobic region, forming a gel by hydrophilic-hydrophobic interaction. Since the hydrophilic-hydrophobic interaction is weak, it can be dynamically destroyed and reconstructed under shear force, thus showing a certain degree of injectability and self-healing properties. After the shear force is removed, a gel can be quickly formed ( Figure 2). In the presence of ROS, the ROS-responsive functional groups break, the ABA-type amphiphilic triblock polymer breaks, decomposes to form a hydrophobic domain and a hydrophilic solution, and the gel disperses, achieving the release of drug molecules.

[0020] In the preparation process of the present invention, injectable hydrogels with different properties can be obtained by changing corresponding parameters such as the composition of each block molecule of the ABA triblock molecule, the molecular weight, the concentration of solution assembly, etc.

[0021] Compared with the prior art, the present invention has the following beneficial effects: The present invention combines hydrophilic, hydrophobic and reactive oxygen responsive functional groups through a modular method to synthesize a multi-block amphiphilic polymer with reactive oxygen responsiveness, and obtains an assembly with a spherical or nanofiber microphase structure by controlling the solution assembly conditions to form a gel. The hydrogel has a strength of 1Pa-1MPa, can load drugs of different properties such as hydrophilicity and hydrophobicity, and has injectability and in vivo reactive oxygen responsiveness function, has adaptability to reactive oxygen concentration, and can selectively and intelligently control the release of drugs according to different reactive oxygen concentrations in the body of 10μM-1000μM, and can be decomposed in 3-20 days. The use of the hydrogel of the present invention can improve the accuracy of disease treatment and realize the intelligent and accurate release of drugs. The gel has high biocompatibility, biomedical safety, and degradability. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the structure of triblock polymer, preparation of injectable hydrogel and its self-assembly structure; Figure 2 Schematic diagram of the molecular structure change mechanism of hydrogel injectability; Figure 3 The synthetic chemical structure of the ABA-type amphiphilic triblock polymer of Example 1; Figure 4 The synthetic chemical structure of the ABA-type amphiphilic triblock polymer of Example 2; Figure 5 The synthetic chemical structure of the ABA-type amphiphilic triblock polymer of Example 3; Figure 6 Rheological data of different assembly structures. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope limited by the appended claims of the application. All raw materials used in the embodiments are commercially available unless otherwise specified.

[0024] Example 1 Polypolyhedral silsesquioxane is used as the hydrophobic block molecule, and polyethylene oxide is used as the hydrophilic block molecule. The molecular weight of polyethylene oxide is M n = 20000 g / mol, using ketone thioether as the ROS response functional group, the synthetic chemical reaction formula is as follows Figure 3 As shown, an ABA type amphiphilic triblock polymer is obtained, and the mass of the hydrophobic block molecule is 10wt.% of the ABA type amphiphilic triblock polymer.

[0025] The specific synthesis method of the ABA type amphiphilic triblock polymer is as follows: Figure 3 ): The commercial POSS-NH 2 As raw material, the esterification method was used to react with the carboxyl group in the reported reactive oxygen response functional group (ROS-linker) to synthesize POSS-ROS linker-COOH, which was then esterified with 2-azidoethanol to generate POSS-ROS linker-N 3 , POSS-ROS linker-N 3 The final product POSS-ROS linker-PEO-ROS linker-POSS was obtained by reacting with commercially available polyethylene oxide containing alkynyl functional groups at both ends of the molecular chain.

[0026] The POSS-ROS linker-COOH synthesis method: BPOSS-NH 2 The equivalent is 1; the equivalent of ROS-linker is 1; the equivalent of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) is 1; the catalyst 4-dimethylaminopyridine (DMPA) is added, the equivalent is 0.01; anhydrous dichloromethane (DCM) is added as the reaction solvent, and the concentration of the total reactant is 30wt.%; the reaction is carried out at 25°C for 12h. After the reaction is completed, the second component is collected by column chromatography, and the washing liquid is petroleum ether: ethyl acetate = 3:1.

[0027] The POSS-ROS linker-N 3 Synthesis method: POSS-ROS linker-COOH equivalent is 1; 2-azidoethanol equivalent is 1.2; 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) equivalent is 1.2; catalyst 4-dimethylaminopyridine (DMPA) is added, equivalent is 0.01; anhydrous dichloromethane (DCM) is added as the reaction solvent, and the concentration of the total reactant is 30wt.%; react at 25℃ for 12h. After the reaction is completed, the first component is collected by column chromatography, and the washing liquid is petroleum ether: ethyl acetate = 3:1.

[0028] The synthesis method of the POSS-ROS linker-PEO-ROS linker-POSS: In a glove box environment without water and oxygen, the commercially available polyethylene oxide containing alkynyl functional groups at both ends of the molecular chain has an equivalent of 1; the POSS-ROS linker-N 3 The equivalent is 2.4; the equivalent of cuprous bromide (CuBr) and pentamethyldiethylenetriamine (PMDETA) is 0.001; anhydrous toluene (Toluene) is added as the reaction solvent, and the concentration of the total reactant is 30wt.%; the reaction is carried out at 40°C for 24 hours. After the reaction is completed, the second component is collected by column chromatography, and the washing liquid is chloroform: methanol = 10:1.

[0029] The injectable hydrogel is constructed by the solution self-assembly method of ABA-type amphiphilic triblock polymer. During the hydrogel assembly process, drug molecules are loaded simultaneously: the obtained ABA-type molecules are dissolved in N,N-dimethylformamide solution with a concentration of 5wt.%, and 1wt.% of curcumin is added as a hydrophobic drug model. Then high-purity water is injected into the above solution. The high-purity water contains the hydrophilic M13 phage drug as a hydrophilic drug model. The concentration of the hydrophilic drug is 5wt.%, the water injection rate is 5μL / min, and the volume ratio of water injection to solution is 10:1 to obtain the hydrogel. The projection electron microscope image of the hydrogel assembly structure is shown in the following figure. Figure 1 As shown, the assembled structure presents a fibrous structure, and the hydrogel strength is 600Pa ( Figure 6 ), rheological data showed that the hydrogel was injectable ( Figure 6 ), the hydrogel with a volume of 0.5 mL responded to the reactive oxygen concentration of 100 μM-500 μM, completely degraded in 7-15 days, and effectively released the drug.

[0030] Example 2 Polypolyhedral silsesquioxane is used as the hydrophobic block molecule, and polyethylene oxide is used as the hydrophilic block molecule. The molecular weight of polyethylene oxide is M n = 10000 g / mol, using ketone thioether as the ROS response functional group, the synthetic chemical reaction formula is as follows Figure 4 As shown, an ABA type amphiphilic triblock polymer was obtained, and the mass of the hydrophobic block molecule was 18.7 wt.% of the ABA type amphiphilic triblock polymer.

[0031] The specific synthesis method of the ABA type amphiphilic triblock polymer is as follows: Figure 4 ): The commercial POSS-NH 2As raw material, it was reacted with the carboxyl group in the reported reactive oxygen response functional group (ROS-linker) by esterification method to synthesize POSS-ROS linker-COOH, which was then esterified with 3-butyne-1-ol to generate POSS-ROS linker-alkynyl. POSS-ROS linker-alkynyl was reacted with commercially available polyethylene oxide containing azide functional groups at both ends of the molecular chain to obtain the final product POSS-ROS linker-PEO-ROS linker-POSS.

[0032] The synthesis method of the POSS-ROS linker-COOH is the same as that in Example 1.

[0033] The POSS-ROS linker-alkynyl synthesis method comprises the following steps: the POSS-ROS linker-COOH equivalent is 1; the 3-butyn-1-ol equivalent is 1.2; the 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) equivalent is 1.2; the catalyst 4-dimethylaminopyridine (DMPA) is added, the equivalent is 0.01; anhydrous dichloromethane (DCM) is added as the reaction solvent, the concentration of the total reactant is 30wt.%; the reaction is carried out at 25°C for 12h. After the reaction is completed, the first component is collected by column chromatography, and the washing liquid is petroleum ether:ethyl acetate = 10:1.

[0034] The POSS-ROS linker-PEO-ROS linker-POSS synthesis method: in a glove box environment without water and oxygen, the commercially available polyethylene oxide containing azide functional groups at both ends of the molecular chain has an equivalent of 1; the POSS-ROS linker-alkynyl equivalent is 2.4; the equivalents of cuprous bromide (CuBr) and pentamethyldiethylenetriamine (PMDETA) are 0.001; anhydrous toluene (Toluene) is added as a reaction solvent, and the concentration of the total reactant is 30wt.%; the reaction is carried out at 40°C for 24h. After the reaction is completed, the second component is collected by column chromatography, and the washing liquid is chloroform:methanol=10:1.

[0035] The injectable hydrogel is constructed by the solution self-assembly method of ABA-type amphiphilic triblock polymer. During the hydrogel assembly process, drug molecule loading is carried out simultaneously: the obtained ABA-type molecules are dissolved in tetrahydrofuran solution with a concentration of 10wt.%, and 2wt.% of vitamin E is added as a hydrophobic drug model. Then high-purity water is injected into the above solution, and the high-purity water contains a hydrophilic M13 phage drug as a hydrophilic drug model. The hydrophilic drug concentration is 10wt.%, the water injection rate is 10μL / min, and the water injection to solution volume ratio is 5:1. The hydrogel has a strength of 800Pa and is injectable. The hydrogel with a volume of 1mL responds to an active oxygen concentration of 50μM-1000μM, is completely degraded in 5-30 days, and effectively releases the drug.

[0036] Example 3 Polypolyhedral silsesquioxane is used as the hydrophobic block molecule, and polyethylene oxide is used as the hydrophilic block molecule. The molecular weight of polyethylene oxide is M n = 8000 g / mol, using ketone thioether as the ROS response functional group, the synthetic chemical reaction formula is as follows Figure 5 As shown, an ABA type amphiphilic triblock polymer was obtained, and the mass of the hydrophobic block molecule was 12.5wt.% of the ABA type amphiphilic triblock polymer.

[0037] The specific synthesis method of the ABA type amphiphilic triblock polymer is as follows: Figure 5 ): ROS-linker reacts with 3-butyn-1-ol to generate alkynyl-ROS linker-alkynyl, and alkynyl-ROS linker-alkynyl reacts with commercially available polyethylene oxide containing azide functional groups at both ends of the molecular chain to obtain N 3 -PEO-ROS linker-PEO-N 3 ; Commercial POSS-NH containing seven isobutyl groups and one amino functional group was used 2 Esterification with 4-pentynoic acid to form BPOSS-alkynyl; N 3 -PEO-ROS linker-PEO-N 3 Click chemistry reaction with BPOSS-alkynyl gave the final product POSS-PEO-ROS linker-PEO-POSS.

[0038] The alkynyl-ROS linker-alkynyl synthesis method comprises the following steps: the ROS linker equivalent is 1; the 3-butyn-1-ol equivalent is 2.4; the 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) equivalent is 2.4; the catalyst 4-dimethylaminopyridine (DMPA) is added, the equivalent is 0.01; anhydrous dichloromethane (DCM) is added as the reaction solvent, the concentration of the total reactant is 30wt.%; the reaction is carried out at 25°C for 12h. After the reaction is completed, the first component is collected by column chromatography, and the washing liquid is petroleum ether:ethyl acetate = 10:1.

[0039] The N 3 -PEO-ROS linker-PEO-N 3 Synthesis method: The commercially available polyethylene oxide with azide functional groups at both ends of the molecular chain has an equivalent of 1; the alkynyl-ROS linker-alkynyl equivalent is 2.2; the equivalent of cuprous bromide (CuBr) and pentamethyldiethylenetriamine (PMDETA) is 0.001; anhydrous toluene (Toluene) is added as the reaction solvent, and the concentration of the total reactant is 30wt.%; the reaction is carried out at 40°C for 24h. After the reaction is completed, the second component is collected by column chromatography, and the washing liquid is chloroform:methanol = 10:1.

[0040] The POSS-alkynyl synthesis method: POSS-NH 2 The equivalent is 1; the equivalent of 4-pentynoic acid is 1.2; the equivalent of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) is 1.2; the catalyst 4-dimethylaminopyridine (DMPA) is added, the equivalent is 0.01; anhydrous dichloromethane (DCM) is added as the reaction solvent, and the concentration of the total reactants is 30wt.%; the reaction is carried out at 25°C for 12h. After the reaction is completed, the first component is collected by column chromatography, and the washing liquid is petroleum ether: ethyl acetate = 10:1.

[0041] The POSS-PEO-ROS linker-PEO-POSS synthesis method: in a glove box environment without water and oxygen, the commercially available polyethylene oxide with azide functional groups at both ends of the molecular chain has an equivalent of 1; the POSS-alkynyl equivalent is 2.4; the equivalents of cuprous bromide (CuBr) and pentamethyldiethylenetriamine (PMDETA) are 0.001; anhydrous toluene (Toluene) is added as a reaction solvent, and the concentration of the total reactant is 30wt.%; the reaction is carried out at 40°C for 24h. After the reaction is completed, the second component is collected by column chromatography, and the washing liquid is chloroform:methanol=10:1.

[0042] The injectable hydrogel is constructed by the solution self-assembly method of ABA-type amphiphilic triblock polymer. During the hydrogel assembly process, drug molecules are loaded simultaneously: the obtained ABA-type molecules are dissolved in 1,4-dioxane solution at a concentration of 1wt.%, and 0.5wt.% of tert-butylhydroquinone is added as a hydrophobic drug model. Then high-purity water is injected into the above solution, and the high-purity water contains hydrophilic drugs, the drug concentration is 10wt.%, the water injection rate is 20μL / min, and the water injection and solution volume ratio is 2:1. The hydrogel has a strength of 800Pa and is injectable. The hydrogel with a volume of 1mL responds to an active oxygen concentration of 50μM-1000μM, and is completely degraded in 3-30 days. After degradation, the hydrophilic drug is released, and the hydrophobic drug is contained in the nanoparticles formed by the load, which can achieve selective targeting of cells for related treatment.

[0043] Example 4 Commercially available polymethyl methacrylate containing a hydroxyl photoenergy group at one end was used as a hydrophobic block molecule with a molecular weight of M n =5000g / mol, using commercially available polyvinyl pyrrolidone with hydroxyl groups at both ends as the hydrophilic block molecule with a molecular weight of M n =50000 g / mol, using ketone thioether as the ROS response functional group to obtain an ABA type amphiphilic triblock polymer, the mass of the hydrophobic block molecule is 33wt.% of the ABA type amphiphilic triblock polymer, and the synthesis method is referenced to Example 1.

[0044] The injectable hydrogel is constructed by using the ABA type amphiphilic triblock polymer through a solution self-assembly method, and during the hydrogel assembly process, drug molecules are loaded simultaneously: The obtained ABA-type molecules were dissolved in tetrahydrofuran at a concentration of 5wt.%, and 1wt.% of curcumin was added as a hydrophobic drug model. Then, high-purity water was injected into the above solution, and the hydrophilic M13 phage drug contained in the high-purity water was a hydrophilic drug model. The hydrophilic drug concentration was 5wt.%, the water injection rate was 5μL / min, and the water injection to solution volume ratio was 10:1. The hydrogel was obtained, and the hydrogel strength was 300Pa, which was injectable. The hydrogel with a volume of 0.6mL responded to the active oxygen concentration of 50μM-300μM, completely degraded in 7-10 days, and effectively released the drug.

[0045] Example 5 Commercially available polydimethylsiloxane with a hydroxyl group at one end was used as a hydrophobic block molecule with a molecular weight of M n = 2000 g / mol, using commercially available polyvinyl alcohol containing azide at the end of the molecular chain as the hydrophilic block molecule with a molecular weight of M n=20000 g / mol, using phenyl borate as the ROS response functional group to obtain an ABA type amphiphilic triblock polymer, the mass of the hydrophobic block molecule is 16wt.% of the ABA type amphiphilic triblock polymer, and the synthesis method is referenced to Example 1.

[0046] The injectable hydrogel is constructed by using the ABA type amphiphilic triblock polymer through a solution self-assembly method, and during the hydrogel assembly process, drug molecules are loaded simultaneously: The obtained ABA-type molecules were dissolved in tetrahydrofuran solution with a concentration of 5wt.%, and 1wt.% of vitamin E was added as a hydrophobic drug model. Then high-purity water was injected into the above solution. The hydrophilic M13 phage drug contained in the high-purity water was a hydrophilic drug model. The hydrophilic drug concentration was 10wt.%, the water injection rate was 10μL / min, and the volume ratio of water injection to solution was 3:1. The hydrogel was obtained with a strength of 400Pa and was injectable. The hydrogel with a volume of 1mL responded to an active oxygen concentration of 50μM-1000μM, completely degraded in 6-30 days, and effectively released the drug.

[0047] Example 6 Polylactic acid is used as the hydrophobic block molecule, and the molecular weight of polylactic acid is M n =1000g / mol, using polytetrahydrofuran as the hydrophilic block molecule, the molecular weight of polytetrahydrofuran is M n =5000g / mol, using ketone thioether as the ROS response functional group, synthesizing ABABABA...multi-block polymer by condensation polymerization method, the ketone thioether functional group is in the middle of the molecular chain, and obtaining ABA type amphiphilic triblock polymer, the mass of the hydrophobic block molecule is 35wt.% of the ABA type amphiphilic triblock polymer, the synthesis method refers to Example 1.

[0048] The injectable hydrogel is constructed by using the ABA type amphiphilic triblock polymer through a solution self-assembly method, and during the hydrogel assembly process, drug molecules are loaded simultaneously: The obtained ABABABA... type molecules were dissolved in 1,4-dioxane solution with a concentration of 7wt.%, and 1wt.% of tert-butylhydroquinone was added as a hydrophobic drug model. Then high-purity water was injected into the above solution. The high-purity water contained hydrophilic drugs with a drug concentration of 10wt.%, a water injection rate of 20μL / min, and a water injection to solution volume ratio of 5:1. The hydrogel was obtained with a strength of 500Pa and injectability. The hydrogel with a volume of 1mL responded to an active oxygen concentration of 50μM-1000μM and was completely degraded in 3-20 days. After degradation, the hydrophilic drugs were released, and the hydrophobic drugs were loaded into the nanoparticles formed, which can achieve selective targeting of cells for related treatments.

[0049] Example 7 The reported RAFT polymerization method was used to obtain polystyrene-polyacrylic acid-trithioester-polyacrylic acid-polystyrene as an ABA-shaped polymer ( Adv. Sci. 2022, 9 , e2105764), polystyrene is a hydrophobic block molecule with a molecular weight of M n =10000g / mol, polyacrylic acid is a hydrophilic block molecule with a molecular weight of M n =20000 g / mol, trithioester is the ROS responsive functional group, and an ABA type amphiphilic triblock polymer is obtained, and the mass of the hydrophobic block molecule is 50wt.% of the ABA type amphiphilic triblock polymer.

[0050] The injectable hydrogel is constructed by using the ABA type amphiphilic triblock polymer through a solution self-assembly method, and during the hydrogel assembly process, drug molecules are loaded simultaneously: The obtained ABA-type molecules were dissolved in N, N-dimethylformamide solution with a concentration of 7wt.%, and 0.5wt.% of vitamin E was added as a hydrophobic drug model. Then high-purity water was injected into the above solution. The hydrophilic M13 phage drug contained in the high-purity water was a hydrophilic drug model. The concentration of the hydrophilic drug was 1wt.%, the injection rate was 20μL / min, and the volume ratio of water injection to solution was 4:1. The hydrogel was obtained with a strength of 500Pa and was injectable. The hydrogel with a volume of 1mL responded to an active oxygen concentration of 20μM-1000μM, completely degraded in 5-30 days, and effectively released the drug.

[0051] Example 8 Commercially available polydimethylsiloxane with hydroxyl groups at the end was used as the hydrophobic block molecule with a molecular weight of M n = 2000 g / mol, using commercially available polyethylene oxide with hydroxyl groups at the end of the molecular chain as the hydrophilic block molecule, with a molecular weight of M n = 2000 g / mol, using the reported ketone thioether containing hydroxyl groups at both ends as the response functional group, using hexamethylene diisocyanate as the condensation activator, the equivalent ratio of polydimethylsiloxane, polyethylene oxide, ketone thioether, and hexamethylene diisocyanate is 1:1:1:1 at 120 o The polymerization reaction was carried out under conditions C to obtain an ABABABA... type amphiphilic multi-block polymer, wherein the mass of the hydrophobic block molecule was 50wt.% of the ABABABA... type amphiphilic tri-block polymer.

[0052] The injectable hydrogel is constructed by using the solution self-assembly method of the ABABABA... type amphiphilic triblock polymer, and during the hydrogel assembly process, drug molecules are loaded simultaneously: The obtained ABABABA... type molecules were dissolved in tetrahydrofuran solution with a concentration of 10wt.%, and 2wt.% of vitamin E was added as a hydrophobic drug model. Then high-purity water was injected into the above solution. The hydrophilic glucose contained in the high-purity water was a hydrophilic drug model. The concentration of the hydrophilic drug was 10wt.%, the injection rate was 15μL / min, and the volume ratio of water injection to solution was 5:1. The hydrogel was obtained with a strength of 700Pa and was injectable. The hydrogel with a volume of 1mL responded to an active oxygen concentration of 30μM-1000μM, completely degraded in 4-20 days, and effectively released the drug.

Claims

1. An injectable hydrogel with active oxygen responsiveness, characterized in that: ABA-type amphiphilic triblock polymers with active oxygen-responsive functional groups form injectable hydrogels loaded with drugs through solution self-assembly; In the ABA type amphiphilic triblock polymer, A is a hydrophobic block molecule, B is a hydrophilic block molecule, and the active oxygen responsive functional group is connected between the hydrophobic block molecules.

2. A method for preparing the injectable hydrogel having active oxygen responsiveness according to claim 1, characterized in that: The following steps are involved: (1) The hydrophobic block molecules, hydrophilic block molecules and active oxygen response functional groups are reacted by esterification reaction, amidation reaction and "click chemistry" reaction to obtain an ABA-type amphiphilic triblock polymer with ROS response ability; (2) The injectable hydrogel is constructed by a solution self-assembly method using an ABA-type amphiphilic triblock polymer, and drug molecules are loaded simultaneously during the hydrogel assembly process.

3. The method for preparing an injectable hydrogel having active oxygen responsiveness according to claim 2, characterized in that: The hydrophobic block molecules include polypolyhedral silsesquioxane, polymethyl methacrylate, polyethyl acrylate, polydimethylsiloxane, polylactic acid, polystyrene, polycaprolactone or polylactide.

4. The method for preparing an injectable hydrogel having active oxygen responsiveness according to claim 2, characterized in that: The hydrophilic block molecule includes polyethylene oxide, polyvinyl pyrrolidone, polyacrylamide, polyvinyl alcohol, polytetrahydrofuran, polyethylene imine, poly(2-ethyl-2-oxazoline), polyvinyl pyridine or polyacrylic acid.

5. The method for preparing an injectable hydrogel having active oxygen responsiveness according to claim 2, characterized in that: The active oxygen responsive functional groups include ketone thioether, phenyl borate ester, selenium-selenium bond, tellurium-tellurium bond, thioether bond, and trithioester bond.

6. The method for preparing an injectable hydrogel having active oxygen responsiveness according to claim 2, characterized in that: The specific operation of the solution self-assembly is as follows: a. dissolving an ABA type amphiphilic triblock polymer in an organic solvent to obtain an ABA solution; the organic solvent comprises N, N-dimethylformamide, dimethyl sulfoxide, 1,4-dioxane or tetrahydrofuran; b. Add water to the ABA solution to induce polymer self-assembly to obtain a hydrogel, and perform dialysis to remove the organic solvent to obtain the injectable hydrogel.

7. The method for preparing an injectable hydrogel having active oxygen responsiveness according to claim 6, characterized in that: The drug molecules include hydrophobic drugs and hydrophilic drugs. The specific operation of drug molecule loading is as follows: the hydrophobic drug and the ABA-type amphiphilic triblock polymer are dissolved in an organic solvent; the hydrophilic drug is dissolved in the water described in step b, and an injectable hydrogel loaded with drug molecules can be obtained.

8. The method for preparing an injectable hydrogel having active oxygen responsiveness according to claim 6, characterized in that: The mass concentration of the organic solution of the ABA type amphiphilic triblock polymer is 0.01wt.%-50wt.%.

9. The method for preparing an injectable hydrogel having active oxygen responsiveness according to claim 6, characterized in that: The volume ratio of water added in step b to ABA solution is 10:1-1:10, the dripping rate of water is 0.01 μL / min-1 mL / min, and the water is pure water or physiological saline; the dialysis method is to add pure water or physiological saline to the hydrogel, change the water every 10-12 hours, and dialyze for 3-4 days.

10. An application of the injectable hydrogel with active oxygen responsiveness according to claim 1, characterized in that: The hydrogel is used as a drug delivery system, loaded with hydrophilic drugs and / or hydrophobic drugs, and is injectable. The hydrogel is in the state before and after injection, and the adaptive release of drugs is achieved in vivo according to the level of tissue active oxygen.

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