PVA-sodium alginate hydrogel containing hydrogen peroxide, preparation method thereof and antibacterial agent

Abstract

The present invention relates to the technical field of polymer materials, and in particular, to a PVA-sodium alginate hydrogel containing hydrogen peroxide, a preparation method thereof, and an antibacterial agent; the preparation method comprises: dropping a hydrogen peroxide solution into a PVA-sodium alginate mixed solution to obtain a hydrogen peroxide mixed solution; dropping the hydrogen peroxide mixed solution into a calcium chloride solution under stirring, and continuously stirring for a set time to perform a cross-linking reaction. The preparation method is suitable for a PVA-sodium alginate hydrogel-coated peroxidizer, which improves the stability of hydrogen peroxide and enables the hydrogen peroxide to be stably and slowly released, that is, the release of hydrogen peroxide is controllable.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, in particular to a PVA-sodium alginate hydrogel containing hydrogen peroxide and a preparation method and an antibacterial agent thereof. Background Art

[0002] Hydrogel is a three-dimensional network structure polymer material containing a large amount of water. It has good biocompatibility and physical properties similar to biological soft tissue. Hydrogen peroxide (H2O2) is an important chemical that can be used in disinfection, bleaching, water treatment and chemical synthesis. However, hydrogen peroxide is unstable and decomposes quickly, which limits its application scenarios.

[0003] In order to expand the application of hydrogen peroxide, the related art uses hydrogel to encapsulate hydrogen peroxide; however, the hydrogel of the related art has limited effect on improving the stability of hydrogen peroxide, and there is a problem of uncontrollable release of hydrogen peroxide. Summary of the invention

[0004] The object of the present invention is to provide a PVA-sodium alginate hydrogel containing hydrogen peroxide, a preparation method thereof and an antibacterial agent. The preparation method is suitable for coating a peroxidizer with the PVA-sodium alginate hydrogel, thereby improving the stability of hydrogen peroxide and enabling the hydrogen peroxide to be released stably and slowly, that is, making the release of hydrogen peroxide controllable.

[0005] The present invention is achieved in that:

[0006] In a first aspect, the present invention provides a method for preparing a PVA-sodium alginate hydrogel containing hydrogen peroxide, comprising:

[0007] Adding a hydrogen peroxide solution dropwise into a PVA-sodium alginate mixed solution to prepare a hydrogen peroxide mixed solution;

[0008] The hydrogen peroxide mixed solution is added dropwise to the calcium chloride solution under stirring, and stirring is continued for a set time to perform a cross-linking reaction.

[0009] In an optional embodiment, before and after the hydrogen peroxide mixed solution is added dropwise to the calcium chloride solution, the stirring speed of the calcium chloride solution is 450-550 rpm.

[0010] In an optional embodiment, the hydrogen peroxide mixed solution is added dropwise to the stirred calcium chloride solution at a dripping rate of 1.5-2.5 mL / min.

[0011] In an optional embodiment, the setting time is 15-60 minutes.

[0012] In an optional embodiment, the mass concentration of the calcium chloride solution is 4-6%.

[0013] In an optional embodiment, the mass concentration of hydrogen peroxide in the hydrogen peroxide mixed solution is 3-7%.

[0014] In an optional embodiment, the preparation method of the PVA-sodium alginate mixed solution includes: mixing equal volumes of PVA solution and sodium alginate solution, wherein the mass concentration of the PVA solution is 3-7%, and the mass concentration of the sodium alginate solution is 1-3%.

[0015] In an optional embodiment, the mass concentration of the PVA solution is 4-6%, and the mass concentration of the sodium alginate solution is 1.5-2.5%.

[0016] In a second aspect, the present invention provides a PVA-sodium alginate hydrogel containing hydrogen peroxide, which is prepared by the method for preparing a PVA-sodium alginate hydrogel containing hydrogen peroxide according to any one of the aforementioned embodiments.

[0017] In a third aspect, the present invention provides an antibacterial agent, comprising a pH regulator and the PVA-sodium alginate hydrogel containing hydrogen peroxide according to the aforementioned embodiment, wherein the pH regulator is used to control the pH of the sustained-release environment of the PVA-sodium alginate hydrogel containing hydrogen peroxide to be 7.0-8.0.

[0018] The beneficial effects of the preparation method of the PVA-sodium alginate hydrogel containing hydrogen peroxide of the present invention include: the preparation method of the present invention utilizes the PVA-sodium alginate hydrogel composite system to efficiently encapsulate hydrogen peroxide, which can improve the effectiveness of hydrogen peroxide coating, thereby improving the stability of hydrogen peroxide coating, and at the same time, the PVA-sodium alginate hydrogel of the composite system has a more excellent network structure, which can effectively realize the slow and continuous release of hydrogen peroxide. Moreover, the preparation method of the present invention adopts physical mixing and ionic cross-linking, which is simple, easy to operate, and easy to achieve large-scale production.

[0019] The beneficial effects of the hydrogen peroxide-containing PVA-sodium alginate hydrogel of the present invention include: improving the stability of hydrogen peroxide encapsulation and enabling the hydrogen peroxide to be released stably and slowly, that is, making the release of hydrogen peroxide controllable.

[0020] The beneficial effects of the antibacterial agent of the present invention include: the antibacterial agent of the present invention uses a pH regulator to control the pH of the sustained-release environment of the PVA-sodium alginate hydrogel containing hydrogen peroxide to 7.0-8.0, which can effectively improve the release stability of hydrogen peroxide. DETAILED DESCRIPTION

[0021] 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.

[0022] The present disclosure provides a method for preparing a PVA-sodium alginate hydrogel containing hydrogen peroxide, comprising:

[0023] The hydrogen peroxide solution is added dropwise to the PVA-sodium alginate mixed solution to prepare a hydrogen peroxide mixed solution; the hydrogen peroxide mixed solution is added dropwise to the calcium chloride solution in a stirring state, and the stirring is continued for a set time to perform a cross-linking reaction.

[0024] The PVA-sodium alginate hydrogel composite system is used to efficiently encapsulate hydrogen peroxide, which can improve the effectiveness of hydrogen peroxide coating, and then improve the stability of hydrogen peroxide coating. At the same time, the PVA-sodium alginate hydrogel of the composite system has a more excellent network structure, which can effectively achieve slow and continuous release of hydrogen peroxide. Moreover, the preparation method of the present invention adopts physical mixing and ion cross-linking, which is simple, easy to operate, and easy to achieve large-scale production.

[0025] Optionally, before and after the hydrogen peroxide mixed solution is added dropwise to the calcium chloride solution, the stirring speed of the calcium chloride solution is 450-550rpm, for example: 450rpm, 470rpm, 500rpm, 520rpm, 550rpm, etc., which are not specifically limited here. Optimizing the stirring rate can ensure the effective cross-linking reaction, ensure the uniform distribution of the particle size of the hydrogel particles formed by cross-linking, and ensure the mechanical strength of the hydrogel particles, thereby ensuring the stable sustained release effect of hydrogen peroxide. If the stirring speed is less than 450rpm, the uniformity of the particle size of the hydrogel particles cannot be guaranteed; if the stirring rate is greater than 550rpm, it is easy to cause decomposition and loss of hydrogen peroxide during the cross-linking process.

[0026] Optionally, the dripping rate of the hydrogen peroxide mixed solution when dripping into the calcium chloride solution under stirring is 1.5-2.5mL / min, for example: 1.5mL / min, 1.8mL / min, 2.0mL / min, 2.3mL / min, 2.5mL / min, etc., which are not specifically limited here. Optimizing the dripping speed of the hydrogen peroxide mixed solution is conducive to obtaining a more regular hydrogel microsphere morphology and making the particle size of the hydrogel microspheres uniformly distributed, that is, ensuring that the particle size of the hydrogel microspheres formed by cross-linking is not much different, and ensuring that the hydrogel microspheres are not prone to adhesion. If the dripping rate is less than 1.5mL / min, it is easy to cause adhesion between the hydrogel microspheres, and thus it is impossible to ensure the stable release of hydrogen peroxide; if the dripping rate is greater than 2.5mL / min, it is easy to cause adverse effects on cross-linking, and even fail to effectively achieve cross-linking.

[0027] Optionally, the time is set to 15-60 min, for example: 15 min, 20 min, 25 min, 30 min, 35 min, 45 min, 60 min, etc., which are not specifically limited here. Optimizing the cross-linking time can improve the encapsulation rate of hydrogen peroxide on the one hand, and on the other hand, it can improve the mechanical strength of the formed hydrogel microspheres to ensure the subsequent stable sustained release of hydrogen peroxide.

[0028] Furthermore, the time is set to 25-35 minutes; cross-linking according to the above time can reliably take into account both the mechanical strength of the hydrogel microspheres and the encapsulation rate of hydrogen peroxide.

[0029] Optionally, the calcium chloride used to prepare the calcium chloride solution is analytically pure, and the mass concentration of the calcium chloride solution is 4-6%, for example: 4%, 5%, 6%, etc., which is not specifically limited here. Optimizing the mass concentration of the calcium chloride solution can improve the efficiency and mechanical strength of the hydrogel microspheres formed, and improve the encapsulation rate of hydrogen peroxide.

[0030] Furthermore, the mass concentration of calcium chloride is 5%.

[0031] Optionally, the mass concentration of hydrogen peroxide in the hydrogen peroxide mixed solution is 3-7%, for example: 3%, 4%, 5%, 6%, 7%, etc., which is not specifically limited here. Optimizing the content of hydrogen peroxide in the hydrogen peroxide mixed solution can increase the hydrogen peroxide encapsulation rate in the hydrogel microspheres finally formed by cross-linking and reduce the loss of hydrogen peroxide.

[0032] Optionally, when preparing the hydrogen peroxide mixed solution, the mass percentage of the hydrogen peroxide solution added dropwise to the PVA-sodium alginate mixed solution may be 30%.

[0033] Of course, in other embodiments, when preparing the hydrogen peroxide mixed solution, the mass percentage of the hydrogen peroxide solution added dropwise to the PVA-sodium alginate mixed solution can be 20%, 50%, etc., which is not specifically limited here.

[0034] Optionally, the preparation method of the PVA-sodium alginate mixed solution includes: mixing equal volumes of PVA solution and sodium alginate solution, wherein the mass concentration of the PVA solution is 3-7% (for example: 3%, 4%, 5%, 6%, 7%, etc., not specifically limited here), and the mass concentration of the sodium alginate solution is 1-3% (for example: 1%, 2%, 3%).

[0035] Optimizing the mass concentration of the PVA (polyvinyl alcohol) solution can ensure that the hydrogel microspheres have good mechanical strength, thereby ensuring the stable release of hydrogen peroxide; if the mass concentration of PVA is too high, the water content of the hydrogel microspheres will be significantly reduced. Optimizing the mass concentration of the sodium alginate solution can improve the network density of the hydrogel to ensure the reliable encapsulation effect of hydrogen peroxide and ensure the stable and sustained release of hydrogen peroxide.

[0036] Optionally, the mass concentration of the PVA solution is 4-6%; the mass concentration of the sodium alginate solution is 1.5-2.5%. At this concentration, a good hydrogen peroxide encapsulation rate and sustained release effect can be ensured.

[0037] Optionally, polyvinyl alcohol (PVA): molecular weight 88000-97000, hydrolysis degree 98-99%; sodium alginate can be selected from medium viscosity grades.

[0038] Optionally, hydrogen peroxide can also be encapsulated in the PVA-sodium alginate mixed hydrogel system together with plant essential oil or antibacterial essential oil.

[0039] It should be noted that the PVA-sodium alginate hydrogel composite system used in the PVA-sodium alginate hydrogel containing hydrogen peroxide disclosed in the present invention also has good biocompatibility, and can be used in the biomedical field, as well as in multiple fields such as air purification, food preservation, and water treatment. For example, the deodorization module added to the refrigerator utilizes the sustained-release characteristics of hydrogen peroxide to enhance the cleaning and antibacterial effect of the refrigerator.

[0040] It should also be noted that the microspheres obtained after the cross-linking reaction can be repeatedly washed with deionized water to remove calcium chloride, and then kept in a refrigerator (about 4°C).

[0041] The present disclosure also provides an antibacterial agent, which includes a pH regulator and a PVA-sodium alginate hydrogel containing hydrogen peroxide prepared by the above-mentioned method for preparing the PVA-sodium alginate hydrogel containing hydrogen peroxide. The pH regulator is used to control the pH of the sustained-release environment of the PVA-sodium alginate hydrogel containing hydrogen peroxide to be 7.0-8.0.

[0042] The pH of the sustained-release environment of the PVA-sodium alginate hydrogel containing hydrogen peroxide is controlled to be 7.0-8.0 by using a pH regulator, which can effectively improve the release stability of hydrogen peroxide.

[0043] The present invention is further described in detail below in conjunction with embodiments.

[0044] Example 1

[0045] 1) PVA powder and deionized water are used to prepare a PVA solution with a mass concentration of 5%; wherein, after the PVA powder is added to the deionized water, it is heated and stirred in a water bath at 80° C. for 4 hours until the PVA is dissolved, and then cooled to obtain the PVA solution.

[0046] 2) Sodium alginate powder and deionized water were mixed and stirred at room temperature for 2 hours to prepare a sodium alginate solution with a mass concentration of 2%.

[0047] 3) Mix equal volumes of PVA solution and sodium alginate solution and stir for 30 minutes; then add 30% w / w hydrogen peroxide solution dropwise to the PVA-sodium alginate mixed solution until the hydrogen peroxide concentration reaches 5% w / v, and stir for 30 minutes in an ice bath to ensure uniform mixing, thereby obtaining a hydrogen peroxide mixed solution.

[0048] 4) While the 5% w / v calcium chloride solution was being stirred (stirring rate was 500 rpm), the hydrogen peroxide mixed solution was added dropwise (dropping rate was 2 mL / min) into the calcium chloride solution and stirring was continued for 30 min to fully crosslink the microspheres.

[0049] Example 2

[0050] 1) PVA powder and deionized water are used to prepare a PVA solution with a mass concentration of 3%; wherein, after the PVA powder is added to the deionized water, it is heated and stirred in a water bath at 80° C. for 4 hours until the PVA is dissolved, and then cooled to obtain the PVA solution.

[0051] 2) Sodium alginate powder and deionized water were mixed and stirred at room temperature for 2 hours to prepare a sodium alginate solution with a mass concentration of 1%.

[0052] 3) Mix equal volumes of PVA solution and sodium alginate solution and stir for 30 minutes; then add 30% w / w hydrogen peroxide solution dropwise to the PVA-sodium alginate mixed solution until the hydrogen peroxide concentration reaches 3% w / v, and stir for 30 minutes in an ice bath to ensure uniform mixing, thereby obtaining a hydrogen peroxide mixed solution.

[0053] 4) While the 4% w / v calcium chloride solution was being stirred (stirring rate was 450 rpm), the hydrogen peroxide mixed solution was added dropwise (dropping rate was 1.5 mL / min) into the calcium chloride solution and stirring was continued for 15 min to fully crosslink the microspheres.

[0054] Example 3

[0055] 1) PVA powder and deionized water are used to prepare a PVA solution with a mass concentration of 7%; wherein, after the PVA powder is added to the deionized water, it is heated and stirred in a water bath at 80° C. for 4 hours until the PVA is dissolved, and then cooled to obtain the PVA solution.

[0056] 2) Sodium alginate powder and deionized water were mixed and stirred at room temperature for 2 hours to prepare a sodium alginate solution with a mass concentration of 3%.

[0057] 3) Mix equal volumes of PVA solution and sodium alginate solution and stir for 30 minutes; then add 30% w / w hydrogen peroxide solution dropwise to the PVA-sodium alginate mixed solution until the hydrogen peroxide concentration reaches 7% w / v, and stir for 30 minutes in an ice bath to ensure uniform mixing, thereby preparing a hydrogen peroxide mixed solution.

[0058] 4) While the 6% w / v calcium chloride solution was being stirred (stirring rate was 550 rpm), the hydrogen peroxide mixed solution was added dropwise (dropping rate was 2.5 mL / min) into the calcium chloride solution and stirring was continued for 60 min to fully crosslink the microspheres.

[0059] Example 4

[0060] 1) PVA powder and deionized water are used to prepare a PVA solution with a mass concentration of 6%. After the PVA powder is added to the deionized water, it is heated and stirred in a water bath at 80° C. for 4 hours until the PVA is dissolved, and then cooled to obtain the PVA solution.

[0061] 2) Sodium alginate powder and deionized water were mixed and stirred at room temperature for 2 hours to prepare a sodium alginate solution with a mass concentration of 1.5%.

[0062] 3) Mix equal volumes of PVA solution and sodium alginate solution and stir for 30 minutes; then add 30% w / w hydrogen peroxide solution dropwise to the PVA-sodium alginate mixed solution until the hydrogen peroxide concentration reaches 5% w / v, and stir for 30 minutes in an ice bath to ensure uniform mixing, thereby obtaining a hydrogen peroxide mixed solution.

[0063] 4) While the 5% w / v calcium chloride solution was being stirred (stirring rate was 500 rpm), the hydrogen peroxide mixed solution was added dropwise (dropping rate was 2 mL / min) into the calcium chloride solution and stirring was continued for 30 min to fully crosslink the microspheres.

[0064] Example 5

[0065] 1) PVA powder and deionized water are used to prepare a PVA solution with a mass concentration of 4%; wherein, after the PVA powder is added to the deionized water, it is heated and stirred in a water bath at 80° C. for 4 hours until the PVA is dissolved, and then cooled to obtain the PVA solution.

[0066] 2) Sodium alginate powder and deionized water were mixed and stirred at room temperature for 2 hours to prepare a sodium alginate solution with a mass concentration of 2.5%.

[0067] 3) Mix equal volumes of PVA solution and sodium alginate solution and stir for 30 minutes; then add 30% w / w hydrogen peroxide solution dropwise to the PVA-sodium alginate mixed solution until the hydrogen peroxide concentration reaches 5% w / v, and stir for 30 minutes in an ice bath to ensure uniform mixing, thereby obtaining a hydrogen peroxide mixed solution.

[0068] 4) While the 5% w / v calcium chloride solution was being stirred (stirring rate was 500 rpm), the hydrogen peroxide mixed solution was added dropwise (dropping rate was 2 mL / min) into the calcium chloride solution and stirring was continued for 30 min to fully crosslink the microspheres.

[0069] Comparative Example 1

[0070] The difference between Comparative Example 1 and Example 1 is that the stirring rate is 300 rpm; other process parameters refer to Example 1.

[0071] Comparative Example 2

[0072] The difference between Comparative Example 2 and Example 1 is that the stirring rate is 700 rpm; other process parameters refer to Example 1.

[0073] Comparative Example 3

[0074] The difference between Comparative Example 3 and Example 1 is that the dropping rate is 1 mL / min; the other process parameters refer to Example 1.

[0075] Comparative Example 4

[0076] The difference between Comparative Example 4 and Example 1 is that the dropping rate is 3 mL / min; the other process parameters refer to Example 1.

[0077] Comparative Example 5

[0078] The difference between Comparative Example 5 and Example 1 is that chitosan is used instead of the PVA-sodium alginate mixed solution to prepare the hydrogel microspheres, and the mass concentration of chitosan is 5%; other process parameters refer to Example 1.

[0079] Experimental Example 1

[0080] The moisture content of the hydrogel microspheres prepared in each embodiment and comparative example was tested. The testing method was as follows: a certain amount of freshly prepared hydrogel microspheres (W1) were weighed, dried in a vacuum drying oven at 60°C for 24 hours, and the mass of the dried sample (W2) was weighed. The moisture content (%) was calculated as (W1-W2) / W1×100%.

[0081] Experimental Example 2

[0082] The hydrogen peroxide encapsulation rate of the hydrogel microspheres prepared in each embodiment and comparative example was tested. The testing method includes: dissolving the hydrogel microspheres in a phosphate buffer solution (PBS) at pH 7.4, and determining the hydrogen peroxide content in the solution using a potassium permanganate titration method, wherein the encapsulation rate (%) = (the actual encapsulated hydrogen peroxide amount obtained by the test / theoretical amount of hydrogen peroxide added) × 100%.

[0083] Experimental Example 3

[0084] The hydrogen peroxide release effect of the hydrogel microspheres prepared in each embodiment and comparative example was tested. The test method includes: placing a certain amount of hydrogel microspheres in PBS at a temperature of 37°C and a pH of 7.4, sampling at a preset time point (such as 0.5h, 1h, 2h, 4h, 8h, 12h, 24h), and measuring the hydrogen peroxide concentration in the release medium.

[0085] Experimental Example 4

[0086] Dilute the microsphere sample appropriately, take 1-2 drops and place on a glass slide, cover with a coverslip. Adjust the appropriate magnification under the microscope, use a micrometer to measure the diameter of the microspheres, and randomly measure 100 microspheres for each sample; calculate the average particle size and standard deviation, and draw a particle size distribution diagram.

[0087] Data processing: Calculate the average particle size and standard deviation, and draw a particle size distribution diagram to obtain the average particle size of the hydrogel microspheres prepared in each embodiment and comparative example.

[0088] The results of Experimental Examples 1-4 are shown in Table 1.

[0089] Table 1

[0090]

[0091]

[0092] According to Table 1, by optimizing the mass concentration of the PVA solution, the mass concentration of sodium alginate, the stirring rate during cross-linking, and the dripping rate of the hydrogen peroxide mixed solution in Examples 1, 4, and 5, the water content of the prepared hydrogel microspheres can be effectively ensured, the encapsulation rate of hydrogen peroxide can be improved, the particle size of the hydrogel microspheres can be ensured to be average, and the hydrogel microspheres can be stably released.

[0093] By comparing Example 1 and Example 2, it can be seen that when the mass concentration of the PVA solution and the mass concentration of sodium alginate are low and the stirring time during cross-linking is short, the network density of the hydrogel decreases, the mechanical strength of the hydrogel microspheres decreases, the encapsulation rate of hydrogen peroxide decreases, and the release rate of hydrogen peroxide increases.

[0094] By comparing Example 1 and Example 3, it can be seen that when the mass concentration of the PVA solution and the mass concentration of sodium alginate are high and the stirring time during cross-linking is long, the network density of the hydrogel increases, the mechanical strength of the hydrogel microspheres increases, the encapsulation rate of hydrogen peroxide decreases to a certain extent, and the release rate of hydrogen peroxide is too low.

[0095] By comparing Example 1 with Comparative Examples 1 and 2, it can be seen that if the stirring rate during crosslinking is too low, the particle size of the hydrogel microspheres will be uneven (as shown in Table 1 by a larger fluctuation range of the average particle size), while if the stirring rate is too high, it will lead to excessive loss of hydrogen peroxide and reduce the encapsulation rate of hydrogen peroxide.

[0096] By comparing Example 1 with Comparative Examples 3 and 4, it can be seen that if the dropping rate of the hydrogen peroxide mixed solution is too low, the hydrogel microspheres will adhere to each other, the hydrogen peroxide encapsulation rate will be reduced, and the particle size distribution of the hydrogel microspheres will be uneven (as shown in Table 1 by a larger fluctuation range of the average particle size), and the release rate of hydrogen peroxide will be increased; if the dropping rate of the hydrogen peroxide mixed solution is too fast, it will have an adverse effect on crosslinking and reduce the encapsulation rate of hydrogen peroxide.

[0097] By comparing Example 1 and Comparative Example 5, it can be seen that the use of a PVA-sodium alginate mixed solution system to prepare a hydrogel can improve the stability of hydrogen peroxide encapsulation and ensure the stability of hydrogen peroxide release; however, chitosan is difficult to achieve stable encapsulation of hydrogen peroxide and controllable sustained release.

[0098] Experimental Example 5

[0099] The thermal stability of the hydrogel microspheres of Example 1 was tested.

[0100] The hydrogel microspheres of Example 1 were stored at 4° C., 25° C. and 37° C. for a set number of days, and then the hydrogen peroxide content was detected.

[0101] result:

[0102] 1. At 4°C, the hydrogen peroxide content remained above 95% of the initial value after 30 days.

[0103] 2. At 25°C, the hydrogen peroxide content dropped to 85% of the initial value after 30 days.

[0104] 3. Under 37°C conditions, the hydrogen peroxide content decreased significantly after 15 days.

[0105] According to the experimental results, the hydrogel microspheres of Example 1 can maintain stable sustained release at room temperature (about 25° C.).

[0106] Experimental Example 6

[0107] The photostability of the hydrogel microspheres of Example 1 was tested.

[0108] The hydrogel microspheres of Example 1 were stored under light-proof and sunlight-irradiation conditions for 15 days, and the loss of hydrogen peroxide was compared.

[0109] result:

[0110] 1. Under light-proof conditions, the hydrogen peroxide content remained at 92% of the initial value after 15 days.

[0111] 2. Under sunlight conditions, the hydrogen peroxide content dropped to 70% of the initial value after 15 days.

[0112] According to the experimental results, the hydrogel microspheres of Example 1 have a relatively stable sustained release effect regardless of whether under shading or illumination conditions.

[0113] Experimental Example 7

[0114] The antibacterial property of the hydrogel microspheres of Example 1 was tested.

[0115] The hydrogel microspheres of Example 1 were placed in a test solution containing Escherichia coli at 24°C. After 24 hours of treatment, the number of Escherichia coli in the test solution decreased by 99.9%, and the organic matter content (COD value) in the test solution decreased by about 30%.

[0116] Experimental Example 8

[0117] The purification effect of the hydrogel microspheres of Example 1 was tested.

[0118] The hydrogel microspheres of Example 1 were loaded onto a filter element of an air purifier having only non-woven fabric, and then the filter element was assembled into the air purifier and placed in a room with odor. After 12 hours, the odor in the room was significantly reduced.

[0119] Experimental Example 9

[0120] The hydrogel microspheres of Example 1 were placed in PBS buffer solutions with pH values ​​of 5.0, 6.5, and 7.4, respectively, and the hydrogen peroxide release effect of each experimental group was detected according to the method of Experimental Example 3.

[0121] result:

[0122] 1. In PBS buffer solution with a pH of 5.0, the cumulative release of hydrogen peroxide in 24 hours is 88.2%.

[0123] 2. In the PBS buffer solution with a pH of 6.5, the cumulative release of hydrogen peroxide in 24 hours is 75.3%.

[0124] 3. In PBS buffer solution with a pH of 7.4, the cumulative release of hydrogen peroxide in 24 hours is 65.7%.

[0125] According to the results, under the condition of pH 7.4, the hydrogen peroxide encapsulated in the hydrogel microspheres can be stably released; when the pH is too low, the release rate of hydrogen peroxide is too fast.

[0126] In summary, the preparation method of the PVA-sodium alginate hydrogel containing hydrogen peroxide of the present invention can utilize the PVA-sodium alginate hydrogel composite system to efficiently encapsulate hydrogen peroxide, can improve the effectiveness of hydrogen peroxide coating, and then improve the stability of hydrogen peroxide coating, and at the same time, the PVA-sodium alginate hydrogel of the composite system has a more excellent network structure, can effectively achieve the slow and continuous release of hydrogen peroxide; and can also ensure that the prepared PVA-sodium alginate hydrogel containing hydrogen peroxide has good mechanical properties. The preparation method of the present invention is prepared by physical mixing and ionic crosslinking, which is simple, easy to operate, and easy to achieve large-scale production.

[0127] The PVA-sodium alginate hydrogel containing hydrogen peroxide of the present invention can be used to prepare an antibacterial agent, and the pH of the antibacterial agent is controlled to be 7.0-8.0, which can effectively improve the release stability of hydrogen peroxide.

[0128] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a PVA-sodium alginate hydrogel containing hydrogen peroxide, characterized in that: include: Adding a hydrogen peroxide solution dropwise into a PVA-sodium alginate mixed solution to prepare a hydrogen peroxide mixed solution; The hydrogen peroxide mixed solution is added dropwise to the calcium chloride solution in a stirring state, and the stirring is continued for a set time to perform a cross-linking reaction.

2. The method for preparing the PVA-sodium alginate hydrogel containing hydrogen peroxide according to claim 1, characterized in that: Before and after the hydrogen peroxide mixed solution is dropped into the calcium chloride solution, the calcium chloride solution is stirred at a speed of 450-550 rpm.

3. The method for preparing the PVA-sodium alginate hydrogel containing hydrogen peroxide according to claim 1, characterized in that: The dripping rate of the hydrogen peroxide mixed solution when added dropwise to the calcium chloride solution in a stirring state is 1.5-2.5 mL / min.

4. The method for preparing the PVA-sodium alginate hydrogel containing hydrogen peroxide according to claim 1, characterized in that: The setting time is 15-60 minutes.

5. The method for preparing the PVA-sodium alginate hydrogel containing hydrogen peroxide according to claim 1, characterized in that: The mass concentration of the calcium chloride solution is 4-6%.

6. The method for preparing the PVA-sodium alginate hydrogel containing hydrogen peroxide according to claim 1, characterized in that: The mass concentration of the hydrogen peroxide in the hydrogen peroxide mixed solution is 3-7%.

7. The method for preparing the PVA-sodium alginate hydrogel containing hydrogen peroxide according to claim 1, characterized in that: The preparation method of the PVA-sodium alginate mixed solution comprises: mixing equal volumes of PVA solution and sodium alginate solution, wherein the mass concentration of the PVA solution is 3-7%, and the mass concentration of the sodium alginate solution is 1-3%.

8. The method for preparing the PVA-sodium alginate hydrogel containing hydrogen peroxide according to claim 7, characterized in that: The mass concentration of the PVA solution is 4-6%, and the mass concentration of the sodium alginate solution is 1.5-2.5%.

9. A PVA-sodium alginate hydrogel containing hydrogen peroxide, characterized in that: The hydrogel is prepared by the method for preparing the PVA-sodium alginate hydrogel containing hydrogen peroxide according to any one of claims 1 to 8.

10. An antibacterial agent, characterized in that The invention comprises a pH regulator and the PVA-sodium alginate hydrogel containing hydrogen peroxide as claimed in claim 9, wherein the pH regulator is used to control the pH of the sustained-release environment of the PVA-sodium alginate hydrogel containing hydrogen peroxide to be 7.0-8.0.

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