Hydrogel dressing for wound repair and preparation method thereof

Abstract

The invention provides a hydrogel dressing for wound repair and a preparation method thereof, and the hydrogel dressing is prepared from the following components in percentage by mass: 4.5 to 6.5 percent of unsaturated sugar-containing ester monomer, 2.0 to 2.5 percent of nonionic soluble cellulose, 7 to 10 percent of methacrylic anhydride quaternary ammonium salt, 18 to 20 percent of butanediol and the balance of water. The preparation method comprises the following steps: coupling beta-D glucose pentaacetate with hydroxyethyl methylacrylate through a condensation reaction to obtain a polymerizable unsaturated sugar-containing ester monomer, and then copolymerizing the polymerizable unsaturated sugar-containing ester monomer with methacrylic anhydride quaternary ammonium salt during preparation of the hydrogel dressing. According to the hydrogel dressing, due to introduction of a hydrophobic component and a polyelectrolyte component, ultrahigh strength and water content can be kept at the same time, and the hydrogel dressing has a remarkable hemostatic effect, excellent antibacterial ability and good cell compatibility and has the potential of serving as a dressing for rapid wound repair.

Description

Technical Field

[0001] The invention relates to the field of medical hydrogel dressings, and in particular to a wound repair hydrogel dressing and a preparation method thereof. Background Art

[0002] Hydrogel is a gel with water as the dispersion medium. By introducing a part of hydrophobic groups and hydrophilic residues into a water-soluble polymer with a network cross-linked structure, the hydrophilic residues combine with water molecules to connect the water molecules inside the network, while the hydrophobic residues swell when they come into contact with water. Hydrogel is a polymer network system that is soft in nature, can maintain a certain shape, and can absorb a large amount of water. All water-soluble or hydrophilic polymers can form hydrogels through certain chemical cross-linking or physical cross-linking.

[0003] According to the different preparation methods of hydrogels, they can be divided into chemical cross-linked hydrogels, radiation cross-linked hydrogels and physical cross-linked hydrogels. Chemical cross-linked hydrogels are hydrogels that form a cross-linked network by adding appropriate cross-linking agents. The hydrogel obtained by this method is permanent, but it has many defects, such as poor optical transparency when the degree of cross-linking is high, low water absorption rate, poor mechanical properties, especially low strength and high brittleness, and the post-treatment of unreacted cross-linking agents added to the system is difficult, so its application is limited. Radiation cross-linked hydrogels are formed by ultraviolet light or r-ray irradiation to form a cross-linked network in the system. This method also introduces impurities into the system, resulting in post-treatment difficulties, which limits its application. Physical cross-linked hydrogels are formed by physical forces such as electrostatic action, hydrogen bonding, chain entanglement, etc. This gel is non-permanent and can be converted into a solution by heating the gel, so it is also called a pseudogel or a thermoreversible gel. Since this type of hydrogel does not need to introduce other components into the system, the resulting hydrogel product is pure; at the same time, since the cross-linking degree of the hydrogel prepared in this way is relatively low and reversible, its application range is greatly expanded.

[0004] Hydrogel dressings have good water absorption and can undergo repeated hydration when in contact with the wound surface. They have the dual functions of providing moisture to the wound surface and absorbing exudate. Hydrogel dressings can promote better wound healing, absorb wound exudate, not adhere to the wound surface, reduce the patient's pain, provide a moist microenvironment for the wound, and have good air permeability and biocompatibility.

[0005] Although there are many hydrogel dressings available and these hydrogel dressings have good application performance, this field has already developed to a relatively mature stage. Further breakthroughs to obtain hydrogel dressings with better performance are currently a difficult problem that needs to be solved. Summary of the invention

[0006] In view of the above, an object of the present invention is to provide a hydrogel dressing for wound repair and a preparation method thereof.

[0007] A wound repair hydrogel dressing, which comprises the following components by mass percentage: 4.5-6.5% of unsaturated sugar-containing ester monomers, 2.0-2.5% of nonionic soluble cellulose, 7-10% of methacrylic anhydride quaternary ammonium salt, 18-20% of butanediol, and the remainder of water; wherein the structure of the methacrylic anhydride quaternary ammonium salt is as shown in Formula I: Formula I In some embodiments of the present invention, the method for preparing the unsaturated sugar-containing ester monomer comprises the following steps: S1: Add β-D-glucose pentaacetate into a reaction bottle filled with an anhydrous organic solvent, stir and dissolve, and fill with inert gas to remove oxygen; S2: Add hydroxyethyl methacrylate and boron trifluoride etherate into the reaction bottle, fill it with inert gas again to deoxygenate, seal the reaction bottle, and react at room temperature for 24-30 hours; S3: After the reaction is completed, the crude product is washed with deionized water, then dehydrated with saturated sodium chloride, dried with a desiccant, and finally further purified using silica gel column chromatography.

[0008] The synthesis route of the unsaturated sugar-containing ester monomer is shown in Formula II: Formula II Furthermore, in S1, the organic solvent is at least one of dichloromethane, chloroform, tetrahydrofuran, and toluene.

[0009] Furthermore, in S1 and S2, the mass volume ratio of β-D-glucose pentaacetate, anhydrous organic solvent, hydroxyethyl methacrylate and boron trifluoride etherate is 5-8g:50-60ml:1.5-2.8ml:5-8ml.

[0010] In some embodiments of the present invention, the nonionic soluble cellulose is at least one of hydroxyethyl cellulose, methyl cellulose and hydroxypropyl cellulose.

[0011] In some embodiments of the present invention, among the non-ionic soluble cellulose, the viscosity of a 2% aqueous solution of hydroxyethyl cellulose at 20°C is 10000-30000 cP; the viscosity of a 2% aqueous solution of methyl cellulose at 20°C is 4000-5000 cP; the viscosity of a 2% aqueous solution of hydroxypropyl cellulose at 20°C is 100-500 cP.

[0012] In some embodiments of the present invention, the hydrogel dressing further comprises 0.1-2.5% of an active ingredient by mass percentage, wherein the active ingredient is selected from at least one of laminin, deproteinized extracellular matrix and growth factor.

[0013] The present invention also provides a method for preparing the above-mentioned wound repair hydrogel dressing, comprising the following steps: Step 1: dissolving unsaturated sugar-containing ester monomers and quaternary ammonium salts of methacrylic anhydride in a polar aprotic solvent, adding an azo polymerization initiator thereto, and after complete dissolution, introducing nitrogen to remove oxygen; shaking to remove bubbles, and reacting at 60-70° C. overnight to obtain a hydrogel precursor; Step 2: uniformly mixing the hydrogel precursor prepared in step 1, butanediol and deionized water to obtain a first mixture; Step 3: Evenly mix the first mixture and the non-ionic soluble cellulose to obtain a second mixture, and adjust the pH of the second mixture to 5.0-7.5 to obtain the hydrogel dressing.

[0014] Furthermore, in the step 1, the polar aprotic solvent is at least one of dimethyl sulfoxide, N,N-dimethylformamide, dimethylacetamide, and N-methylpyrrolidone; in the step 2, the azo polymerization initiator is at least one of azobisisobutyronitrile, azobisisoheptanenitrile, and dimethyl azobisisobutyrate.

[0015] Furthermore, in the step three, after adjusting the pH, irradiation sterilization or moist heat sterilization is also included.

[0016] Beneficial effects: Compared with the prior art, the hydrogel dressing provided by the present invention creatively introduces a hydrogel precursor obtained by polymerization of an unsaturated sugar-containing ester monomer with a specific structure and a quaternary ammonium salt of methacrylic anhydride: the presence of the unsaturated sugar-containing ester monomer structure enhances the mechanical strength of the obtained hydrogel dressing and can maintain stable hydrogen bonds, thereby reducing the size change of the hydrogel dressing; at the same time, based on the hydrophilicity and bactericidal properties of the quaternary ammonium salt structure of methacrylic anhydride, the water absorption performance of the hydrogel dressing is improved and its equilibrium water content is controlled, thereby obtaining excellent hemostatic and antibacterial abilities, ensuring the healing efficiency of wounds, and reducing the formation of scars. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0018] The following is an exemplary description of the preparation process of the unsaturated sugar-containing ester monomer used in the examples: Unsaturated sugar ester monomer-1 S1: Add 5 g of β-D-glucose pentaacetate into a reaction bottle containing 50 ml of anhydrous dichloromethane, stir and dissolve, and fill with nitrogen to remove oxygen; S2: Add 1.5 ml of hydroxyethyl methacrylate and 5 ml of boron trifluoride etherate into the reaction bottle, fill it with nitrogen to deoxygenate, seal the reaction bottle, and react at room temperature for 24 hours; S3: After the reaction is completed, the crude product is washed with deionized water, then dehydrated with saturated sodium chloride, dried with a desiccant, and finally further purified using silica gel column chromatography (the eluent ratio is ethyl acetate: petroleum ether = 3:5).

[0019] Unsaturated sugar ester monomer-2 S1: Add 6.5 g of β-D-glucose pentaacetate into a reaction bottle containing 55 ml of anhydrous tetrahydrofuran, stir and dissolve, and fill with nitrogen to remove oxygen; S2: Add 2.1 ml of hydroxyethyl methacrylate and 7 ml of boron trifluoride etherate into the reaction bottle, fill it with nitrogen to deoxygenate, seal the reaction bottle, and react at room temperature for 28 hours; S3: After the reaction is completed, the crude product is washed with deionized water, then dehydrated with saturated sodium chloride, dried with a desiccant, and finally further purified using silica gel column chromatography (the eluent ratio is ethyl acetate: petroleum ether = 3:5).

[0020] Unsaturated sugar ester monomer-3 S1: Add 8 g of β-D-glucose pentaacetate into a reaction bottle containing 60 ml of anhydrous toluene, stir and dissolve, and fill with nitrogen to remove oxygen; S2: Add 2.8 ml of hydroxyethyl methacrylate and 8 ml of boron trifluoride etherate into the reaction bottle, fill it with nitrogen to deoxygenate, seal the reaction bottle, and react at room temperature for 30 hours; S3: After the reaction is completed, the crude product is washed with deionized water, then dehydrated with saturated sodium chloride, dried with a desiccant, and finally further purified using silica gel column chromatography (the eluent ratio is ethyl acetate: petroleum ether = 3:5).

[0021] Unsaturated sugar ester monomer-4 The preparation process is the same as that of unsaturated sugar-containing ester monomer-1, except that the volume of hydroxyethyl methacrylate used is 1.3 ml.

[0022] Unsaturated sugar ester monomer-5 The preparation process is the same as that of unsaturated sugar-containing ester monomer-3, except that the volume of hydroxyethyl methacrylate used is 3 ml.

[0023] Example 1 Step 1: 6.5% of unsaturated sugar-containing ester monomer-1 and 10% of methacrylic anhydride quaternary ammonium salt are dissolved in dimethyl sulfoxide (DMSO), and 0.5% of azobisisobutyronitrile accounting for the total weight of unsaturated sugar-containing ester monomer-1 and methacrylic anhydride quaternary ammonium salt is added thereto. After the unsaturated sugar-containing ester monomer-1 and methacrylic anhydride quaternary ammonium salt are completely dissolved, nitrogen is introduced to remove oxygen; the mixture is shaken to remove bubbles, and the mixture is reacted at 70° C. overnight to obtain a hydrogel precursor; Step 2: Evenly mix the hydrogel precursor prepared in step 1, 18% butanediol and 64.4% deionized water to obtain a first mixture; Step 3: The first mixture is mixed evenly with 2.0% hydroxyethyl cellulose (purchased from Jufeng Chemical, 2% aqueous solution viscosity is 10000 cP at 20°C) and 0.1% laminin to obtain a second mixture, the pH of the obtained second mixture is adjusted to 7.5, and irradiation sterilized to obtain the hydrogel dressing.

[0024] Example 2 Step 1: 5% of unsaturated sugar-containing ester monomer-2 and 8.5% of methacrylic anhydride quaternary ammonium salt are dissolved in N,N-dimethylformamide (DMF), and 0.5% of azobisisoheptanenitrile accounting for the total weight of unsaturated sugar-containing ester monomer-2 and methacrylic anhydride quaternary ammonium salt is added thereto. After the unsaturated sugar-containing ester monomer-2 and methacrylic anhydride quaternary ammonium salt are completely dissolved, nitrogen is introduced to remove oxygen; the mixture is shaken to remove bubbles, and the mixture is reacted at 65° C. overnight to obtain a hydrogel precursor; Step 2: Evenly mix the hydrogel precursor prepared in step 1, 19% butanediol and 64.3% deionized water to obtain a first mixture; Step 3: The first mixture is mixed evenly with 2.2% hydroxypropyl cellulose (purchased from Jufeng Chemical, 2% aqueous solution viscosity is 350 cP at 20°C) and 1.0% deproteinized extracellular matrix to obtain a second mixture, the pH of the obtained second mixture is adjusted to 7.0, and irradiation sterilized to obtain the hydrogel dressing.

[0025] Example 3 Step 1: 4.5% of unsaturated sugar-containing ester monomer-3 and 7% of methacrylic anhydride quaternary ammonium salt are dissolved in N-methylpyrrolidone (NMP), and 0.5% of dimethyl azobisisobutyrate accounting for the total weight of unsaturated sugar-containing ester monomer-3 and methacrylic anhydride quaternary ammonium salt is added thereto. After complete dissolution, nitrogen is introduced to remove oxygen; the mixture is shaken to remove bubbles, and the mixture is reacted at 60°C overnight to obtain a hydrogel precursor; Step 2: Evenly mix the hydrogel precursor prepared in step 1, 18% butanediol and 66.0% deionized water to obtain a first mixture; Step 3: Mix the first mixture with 2.5% methyl cellulose (purchased from Yunbang Biotechnology, 2% aqueous solution viscosity is 5000 cP at 20°C) and 2.0% growth factor to obtain a second mixture, adjust the pH of the obtained second mixture to 6.5, and sterilize it by wet heat to obtain the hydrogel dressing.

[0026] Example 4 The preparation process is the same as that of Example 1, except that the unsaturated sugar-containing ester monomer-1 is replaced by unsaturated sugar-containing ester monomer-4.

[0027] Example 5 The preparation process is the same as that of Example 3, except that the unsaturated sugar-containing ester monomer-3 is replaced by sugar-containing polymer-5.

[0028] Comparative Example 1 The preparation process is the same as that of Example 3, except that the methacrylic anhydride quaternary ammonium salt is not added.

[0029] Comparative Example 2 The preparation process is the same as that of Example 3, except that the unsaturated sugar-containing ester monomer-3 is not added.

[0030] Performance Testing Swelling rate: The hydrogel sample with a diameter of 5 mm was freeze-dried to constant weight, and its dry weight (m0) was weighed. Then, it was immersed in 6 mL PBS (pH = 7.4). After taking it out with tweezers at regular intervals, the residual water on the surface was removed with absorbent paper and weighed. The weight of the gel at each time point was recorded (m g ), until the water absorption equilibrium is reached, the swelling time is about 120h (n=3). The swelling rate calculation formula is as follows: Swelling ratio (wt%)=(m g -m0) / m0×100% Moisture content: The hydrogel sample with a diameter of 5 mm was freeze-dried to constant weight, and its dry weight (m0) was weighed. Then, it was immersed in 6 mL of deionized water. At regular intervals, it was taken out with tweezers and the water remaining on the surface was removed with absorbent paper. Then, it was weighed and the weight of the gel at each time point was recorded (m g ), until equilibrium is reached, the expansion time is about 120h (n=3). The moisture content is calculated as follows: Water Content (wt%)=(m g -m0) / m0×100% Hemostasis efficiency: The experimental mice were anesthetized and then fixed on a surgical cork board. Fifty percent of the tail was cut off with a scalpel and placed in the air for 15 seconds to ensure normal blood loss. Then, 300 μL of the hydrogel precursor solution pre-polymerized at room temperature for 3 minutes was immediately applied to the bleeding site using a syringe. Fifteen minutes later, the weight of the filter paper that absorbed the blood was measured and compared with the control group (no treatment after cutting the tail). All measurements were repeated 5 times.

[0031] NIH-3T3 cells were cultured in DMEM (GIBCO, Germany) containing 10% newborn calf serum (NBCs; GIBCO) and 1% PS. 2 Culture flasks (Heidelberg, Germany) were cultured at 37°C and 5% CO2 (standard cell culture conditions). In cell culture experiments, cells were washed with phosphate-buffered saline (PBS) and incubated in cell culture flasks with 1 mL of 0.25% trypsin (containing 0.05% EDTA) for 1 min at 37°C. Detached cells were washed with culture medium and collected.

[0032] Before the biological test, the hydrogel was dialyzed in deionized water to remove the residual unpolymerized monomers, and then freeze-dried to remove water. Then, ultraviolet light was irradiated for 30 minutes to remove the residual bacteria in the hydrogel. The sterilized hydrogel was soaked in the above culture medium for 24 hours to obtain the gel extract. The cell compatibility of the hydrogel was detected by the MTT method. Briefly, NIH-3T3 cells were cultured at 6×10 3 / well were inoculated in a 96-well plate, 6 replicate wells were set up, and 100 μL of culture medium was added to each well. After the cells were cultured until they adhered to the wall, different concentrations of extracts were added and incubated with the cells for 24 hours. Further, a sterile thiazolyl blue solution (0.5 mg / mL, 100 μL / well) prepared in advance was added, and the culture medium was replaced with DMSO after continuing to culture for 4 hours, and its absorbance was detected. The cell survival rate is defined by the formula: In the formula, OD experient Represents the absorbance of the well treated with the extract, OD blank Represents the absorbance of blank solvent (DMSO), OD control Represents the absorbance of the wells treated with an equal volume of culture medium but no extract.

[0033] The test results are detailed in Table 1: Table 1 Test results of hydrogel dressings obtained in Examples 1-5 and Comparative Examples 1-2 From the data in Table 1, it can be seen that the hydrogel dressing provided by the present application has excellent swelling rate and water absorption, can provide an excellent moist environment for the wound, and its good hemostatic effect is conducive to the rapid repair of the wound. In addition, the cell survival rate also reflects the good biocompatibility of the hydrogel dressing.

[0034] In a preferred embodiment of the present application, a special preparation method is adopted to avoid the generation of foam during the preparation process, thereby improving the quality of the prepared hydrogel dressing. At the same time, since no foam is generated during the preparation process, the preparation process can be ensured to have a shorter time, thereby ensuring the production efficiency of the enterprise and further ensuring the economic benefits of the enterprise.

Claims

1. A hydrogel dressing for wound repair, characterized in that: According to the mass percentage, it at least comprises the following components: 4.5-6.5% of unsaturated sugar-containing ester monomers, 2.0-2.5% of nonionic soluble cellulose, 7-10% of methacrylic anhydride quaternary ammonium salt, 18-20% of butanediol and the balance of water; wherein the structure of the methacrylic anhydride quaternary ammonium salt is as shown in Formula I: ； Formula I.

2. The wound repair hydrogel dressing according to claim 1, characterized in that: The preparation method of the unsaturated sugar-containing ester monomer comprises the following steps: S1: Add β-D-glucose pentaacetate into a reaction bottle filled with an anhydrous organic solvent, stir and dissolve, and fill with inert gas to remove oxygen; S2: Add hydroxyethyl methacrylate and boron trifluoride etherate into the reaction bottle, fill it with inert gas again to deoxygenate, seal the reaction bottle, and react at room temperature for 24-30 hours; S3: After the reaction is completed, the crude product is washed with deionized water, then dehydrated with saturated sodium chloride, dried with a desiccant, and finally further purified using silica gel column chromatography.

3. The wound repair hydrogel dressing according to claim 2, characterized in that: In S1, the organic solvent is at least one of dichloromethane, chloroform, tetrahydrofuran and toluene.

4. The wound repair hydrogel dressing according to claim 2, characterized in that: In S1 and S2, the mass volume ratio of β-D-glucose pentaacetate, anhydrous organic solvent, hydroxyethyl methacrylate and boron trifluoride etherate is 5-8g:50-60ml:1.5-2.8ml:5-8ml.

5. The wound repair hydrogel dressing according to claim 1, characterized in that: The nonionic soluble cellulose is at least one of hydroxyethyl cellulose, methyl cellulose and hydroxypropyl cellulose.

6. The wound repair hydrogel dressing according to claim 5, characterized in that: Among the non-ionic soluble celluloses, the viscosity of a 2% aqueous solution of hydroxyethyl cellulose at 20°C is 10000-30000 cP; the viscosity of a 2% aqueous solution of methyl cellulose at 20°C is 4000-5000 cP; and the viscosity of a 2% aqueous solution of hydroxypropyl cellulose at 20°C is 100-500 cP.

7. The wound repair hydrogel dressing according to claim 1, characterized in that: Calculated by mass percentage, the invention further comprises 0.1-2.5% of active ingredients, wherein the active ingredients are selected from at least one of laminin, deproteinized extracellular matrix and growth factor.

8. The method for preparing the wound repair hydrogel dressing according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: dissolving unsaturated sugar-containing ester monomers and quaternary ammonium salts of methacrylic anhydride in a polar aprotic solvent, adding an azo polymerization initiator thereto, and after complete dissolution, introducing nitrogen to remove oxygen; shaking to remove bubbles, and reacting at 60-70° C. overnight to obtain a hydrogel precursor; Step 2: uniformly mixing the hydrogel precursor prepared in step 1, butanediol and deionized water to obtain a first mixture; Step 3: Evenly mix the first mixture and the non-ionic soluble cellulose to obtain a second mixture, and adjust the pH of the second mixture to 5.0-7.5 to obtain the hydrogel dressing.

9. The method for preparing the hydrogel dressing for wound repair according to claim 8, characterized in that: In the step 1, the polar aprotic solvent is at least one of dimethyl sulfoxide, N,N-dimethylformamide, dimethylacetamide, and N-methylpyrrolidone; in the step 2, the azo polymerization initiator is at least one of azobisisobutyronitrile, azobisisoheptanenitrile, and dimethyl azobisisobutyrate.

10. The method for preparing the wound repair hydrogel dressing according to claim 8, characterized in that: In the step three, after adjusting the pH, the method further includes irradiation sterilization or moist heat sterilization.

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