Antibacterial chitosan-based non-woven medical material and preparation method thereof

Abstract

The invention discloses a preparation method of an antibacterial chitosan-based non-woven medical material. The preparation method specifically comprises the following steps: S1, pretreatment: dehydrating a chitosan spunlace base material to remove moisture; s2, primary reaction: adding a reactant solution into the pretreated chitosan spunlace base material, fully soaking and then taking out; s3, in-situ generation of nano particles: mixing a reducing agent into the taken-out chitosan spunlace base material, adjusting a reaction mixture to an alkaline state, and reducing a reactant on the surface of chitosan by the reducing agent to generate the antibacterial nano particles in situ; s4, preparing an antibacterial material: washing the material treated in the step S3, and removing redundant liquid in the material to obtain the antibacterial chitosan-based non-woven medical material. A chitosan-based non-woven material is adopted as a substrate, nano-selenium particles are generated through in-situ adsorption and reduction of chitosan in the fabric by means of an in-situ deposition method, and wound healing is promoted and the antibacterial effect is achieved by combining the synergistic effect of the nano-selenium particles and chitosan.

Description

Technical Field

[0001] The invention belongs to the technical field of medical nonwovens, and particularly relates to an antibacterial chitosan-based nonwoven medical material and a preparation method thereof. Background Art

[0002] In the current medical field, bacterial resistance to antibiotics develops at an alarming rate, far exceeding the speed of research and development and market introduction of new antibiotics. The development of this resistance, coupled with the challenges faced by the development of new antibiotic drugs, such as reduced economic returns, long research and development cycles, and strict regulatory guidelines, has led to a scarcity of new antibiotics on the market. Especially in the field of skin defect treatment, wounds caused by trauma or disease are difficult to heal due to difficult-to-treat infections, and the widespread emergence of drug-resistant bacteria has exacerbated this problem. Therefore, it has become particularly urgent to develop new antimicrobial drugs to combat these resistant bacteria. These new drugs need to be able to effectively treat microbial infections while not causing significant cytotoxicity to host tissues.

[0003] In this context, chitosan is considered as a potential antibacterial material due to its similarity to the structure of natural glycosaminoglycans and its ability to promote wound healing. At the same time, nanoselenium, as an emerging antibacterial and anticancer drug, has attracted attention due to its utilization of selenium, an essential trace element for the human body. Selenium is a key component in the formation of selenoproteins, which have important antioxidant functions. In addition, selenium nanoparticles show selective toxicity to bacteria and are able to act on bacteria without harming mammalian cells. Given the presence of selenium as a trace element in the human body, selenium-based nanoparticles may be more easily accepted by human cells and provide the desired antibacterial properties to combat drug-resistant pathogens. Therefore, the development and application of chitosan and nanoselenium provide new strategies and hopes for solving the current problem of drug-resistant bacteria. Summary of the invention

[0004] Based on the above-mentioned problems of the prior art, the present invention provides an antibacterial chitosan-based non-woven medical material and a preparation method thereof, which adopts a chitosan-based non-woven material as a substrate, and utilizes the chitosan in the fabric to be in situ adsorbed and reduced to generate nano-selenium particles through an in-situ deposition method, and combines the synergistic effect of nano-selenium particles and chitosan to promote wound healing and achieve an antibacterial effect.

[0005] The main technical solutions adopted in the present invention are:

[0006] A method for preparing an antibacterial chitosan-based nonwoven medical material comprises the following steps:

[0007] S1 pretreatment: dehydrating the chitosan spunlace substrate to remove moisture;

[0008] S2 initial reaction: adding the reactant solution to the pretreated chitosan spunlace substrate, soaking it fully and then taking it out;

[0009] S3 In-situ generation of nanoparticles: a reducing agent is mixed into the removed chitosan spunlace substrate, the reaction mixture is adjusted to an alkaline state, and the reducing agent reduces the reactants on the surface of the chitosan to generate antibacterial nanoparticles in situ;

[0010] S4 Preparation of antibacterial material: After washing the material treated in step S3, excess liquid in the material is removed to obtain an antibacterial chitosan-based nonwoven medical material.

[0011] Preferably, the specific step of S1 is: dehydrating the chitosan spunlace substrate at a certain temperature for 6 hours to remove excess water in the material.

[0012] Preferably, in S2, Na2SeO3 solution is added to a container containing chitosan spunlace substrate, and the solution is taken out after swelling for 2 hours under constant temperature and oscillation conditions.

[0013] Preferably, the specific steps of S3 are as follows: adding a reducing agent solution and a NaOH solution to the soaked chitosan spunlace substrate, adjusting the reaction mixture to an alkaline state, and reducing the mixture under constant temperature oscillation conditions for 1 hour.

[0014] Preferably, the reducing agent is reduced glutathione.

[0015] Preferably, in S2, the reactant solution is a sodium selenite solution, and the concentration of the sodium selenite solution is 0.5 mmol / L, 3.125 mmol / L, 5 mmol, 12.5 mmol / L or 50 mmol / L.

[0016] Preferably, the molar ratio of the added amount of sodium selenite to reduced glutathione is 1-100:15.

[0017] Preferably, the concentration of the reducing agent solution is 0.1 mol / L, and the concentration of the NaOH solution is 3 mol / L.

[0018] An antibacterial chitosan-based nonwoven medical material is prepared by adopting the preparation method of the antibacterial chitosan-based nonwoven medical material.

[0019] Preferably, the method comprises nano-selenium particles and a chitosan spunlace substrate, wherein the nano-selenium particles are in-situ generated by sodium selenite and reduced glutathione on the surface of the chitosan spunlace substrate.

[0020] Beneficial effects: The present invention provides an antibacterial chitosan-based nonwoven medical material and a preparation method thereof, which has the following advantages:

[0021] (1) The present invention combines the synergistic effect of nano-selenium particles and chitosan. By adjusting the in-situ formation and loading of selenium nanostructures in chitosan spunlace mesh cloth, the nano-particles on the surface of the material are slowly released, thereby achieving an antibacterial effect and promoting wound healing. The antibacterial rate is as high as 97%, and it is non-toxic and has good cell compatibility.

[0022] (2) The present invention is based on chitosan spunlace base fabric material, which makes the material have good air permeability and fluffiness, enriches the types of new multifunctional composite antibacterial medical materials, and provides a new solution for the development of high-end medical materials that can replace imports. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a microscope image of chitosan spunlace nonwoven fabric substrate (45% CS / V);

[0024] Figure 2 This is the SEM image of chitosan spunlace nonwoven fabric substrate (45% CS / V);

[0025] Figure 3 This is the SEM image of the chitosan spunlace nonwoven fabric substrate (45% CS / V) after modification (50mmol / L sodium selenite concentration);

[0026] Figure 4 is the absorbance value of the chitosan spunlace nonwoven fabric substrate of each sample (the blank sample, the sodium selenite concentrations are 0mmol / L, 0.5mmol / L, 5mmol / L and 50mmol / L respectively); DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application are clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0028] Example 1

[0029] An antibacterial chitosan-based nonwoven medical material, the specific steps are as follows:

[0030] S1 pretreatment: dehydrating the chitosan spunlace substrate to remove moisture; specifically, dehydrating the chitosan spunlace material at a certain temperature (37° C.) for 6 hours to remove excess moisture in the material.

[0031] S2 initial reaction: Add the reagent solution to the pretreated chitosan spunlace substrate, soak it fully and then take it out; specifically, in order to adjust the in-situ formation and loading of selenium nanoparticles, add the reagent (Na2Se2O3) solution to the container containing the chitosan spunlace substrate, swell for 2 hours under constant temperature oscillation conditions (temperature 37°C, orbital shaker speed 120r / min) and then take it out. In this Example 1, the amount of Na2Se2O3 solution added is 20ml, which is added three times in total. The concentration of Na2Se2O3 solution is 0.5mmol / L.

[0032] S3 Nanoparticles in situ generation: A reducing agent is mixed into the removed chitosan spunlace substrate, the reaction mixture is adjusted to an alkaline state, and the reducing agent reduces the reactants on the chitosan surface to generate antibacterial nanoparticles in situ. Specifically, a reducing agent solution (reduced glutathione) and a NaOH solution are added to the soaked chitosan spunlace substrate, the reaction mixture is adjusted to an alkaline state (pH 8.8), and reduced for 1 hour under constant temperature oscillation conditions (temperature 37°C, orbital shaker speed 120r / min). Among them, the concentration of the reducing agent solution is 0.1mol / L, the concentration of the NaOH solution is 3mol / L, the amount of reducing agent solution added is 1.5mL, and the amount of NaOH solution added is 20μL.

[0033] S4 Preparation of antibacterial material: After washing the material treated in step S3, remove the excess liquid in the material to obtain an antibacterial chitosan-based non-woven medical material. Specifically, after the reaction is completed, take out the material and wash it in deionized water for 1 minute. Repeat each washing step 5 times with clean water, then gently dry it with absorbent paper, place it in a refrigerator at -18°C for 24 hours, and then freeze-dry the material at -50°C for 3 hours, remove the excess liquid in the material, and store it in a refrigerator at 4°C. In the present invention, the method of removing moisture from the material and the storage method belong to conventional technical means, so they are not described in detail.

[0034] In the present invention, the dehydration time and the dehydration temperature in S1 can be set by those skilled in the art according to actual needs.

[0035] In the present invention, the constant temperature oscillation conditions in S2 and S3 can be set by those skilled in the art according to actual needs.

[0036] In the present invention, the pH value of the alkaline state in S3 can be adjusted by those skilled in the art according to actual needs.

[0037] Example 2: The concentration of the Na2Se2O3 solution in step S2 of Example 1 is replaced with 3.125 mmol / L, and the remaining steps and conditions are the same as those of Example 1.

[0038] Example 3: The concentration of the Na2Se2O3 solution in step S2 of Example 1 is replaced with 5 mmol / L, and the remaining steps and conditions are the same as those of Example 1.

[0039] Example 4: The concentration of the Na2Se2O3 solution in step S2 of Example 1 is replaced with 12.5 mmol / L, and the remaining steps and conditions are the same as those of Example 1.

[0040] Example 5: The concentration of the Na2Se2O3 solution in step S2 of Example 1 is replaced with 50 mmol / L, and the remaining steps and conditions are the same as those of Example 1.

[0041] In a comparative example, the concentration of the Na2Se2O3 solution in step S2 of Example 1 was replaced with 0 mmol / L, and the remaining steps and conditions were the same as those of Example 1.

[0042] The chitosan spunlace substrate used in Examples 1-5 and the comparative example is a 45% CS / V (chitosan / adhesive fiber) nonwoven material, wherein the chitosan spunlace substrate has a specification of 180-310 kDa and a degree of deacetylation of 85% (CS).

[0043] The microstructure morphology of the chitosan spunlace substrate (45% CS / V) used in Examples 1-5 and Comparative Examples before modification is as follows: Figure 1-2 As shown in . Figure 1 It can be seen that the 45% CS / V material has a fluffy structure, which is beneficial for absorbing wound fluid when used in medical materials. The pores are large and the air permeability is good, which is beneficial for blood circulation. The fluffy fiber scaffold is beneficial for cell growth and promotes the growth of wound tissue. Figure 2 It can be seen that the surface of viscose fiber has grooves and is relatively smooth, while the surface of chitosan fiber without grooves is also relatively smooth. The fibers are in a fluffy state, which can promote cell infiltration and blood entry.

[0044] Figure 3 This is the SEM image of the chitosan spunlace substrate (45% CS / V) after modification (50mmol / L sodium selenite concentration). When the chitosan spunlace substrate is modified with Se nanostructures, the basic structure remains basically unchanged compared with the original CS / V material, but the material surface of the chitosan fiber is no longer smooth and is evenly covered with a layer of nano-selenium.

[0045] (1) Comparative test of antibacterial properties

[0046] With reference to GBT20944.3-2008 "Evaluation of antibacterial properties of textiles Part 3 Oscillation method", the antibacterial properties of the antibacterial chitosan-based nonwoven medical materials prepared in Examples 1-4 and the comparative examples were evaluated by the antibacterial rate method. The antibacterial rates of Examples 1-5 and the comparative examples are shown in Table 1.

[0047] Table 1. Antibacterial rate values ​​of each sample

[0048]

[0049] As can be seen from Table 1, the chitosan spunlace materials loaded with nano-selenium in situ prepared in Examples 1-4 have better antibacterial effects on Escherichia coli and Staphylococcus aureus than the unmodified chitosan spunlace materials (comparative example), and the antibacterial rates of Escherichia coli can reach 95.43%-99.99%, and the antibacterial rates of Staphylococcus aureus can reach 99.76%-99.9%. After the samples are modified in Na2SeO3 solution, the antibacterial rates of the samples increase with the increase of the concentration of Na2SeO3 solution. This shows that selenium nanoparticles are toxic to bacteria, thus playing an antibacterial role.

[0050] (2) Comparative test of biocompatibility

[0051] The cytotoxicity of silver-loaded chitosan microspheres was measured by MTT method according to GB / T 14233.2-2005. The chitosan spunlace materials loaded with nano-selenium in situ prepared in Examples 1, 3, and 5 and the comparative example were used as test samples, and mouse L929 fibroblasts were selected as test cells. The absorbance values ​​of each test sample are shown in Figure 4 shown.

[0052] from Figure 4 The following conclusions can be drawn from the analysis:

[0053] (1) The cell OD value of the modified nano-selenium in situ loaded chitosan spunlace material (45% CS / V) after 24 hours was greater than that of the blank sample and the control sample. When the Na2SeO3 concentration was 0.5mmol / L, the cell OD value was lower than that of the blank sample after 4 days, and after 7 days, the remaining cells continued to grow, showing good biocompatibility. Among them, the sample with a Na2SeO3 concentration of 5mmol / L had the best biocompatibility.

[0054] (2) The cell absorbance value (OD value) of the unmodified chitosan spunlace nonwoven fabric substrate (comparative example) after 7 days was higher than that of the blank sample, indicating that materials containing chitosan have a growth-promoting effect on cells.

[0055] (3) At various concentrations of Na2SeO3, cells grown in chitosan spunlace materials loaded with nano-selenium in situ grew slowly at 24 hours. After the time was extended to 4 days and 7 days, the survival rate of L929 cells increased significantly. Therefore, the addition of nano-selenium can improve the biocompatibility of the material. In addition, since the fluffy structure of the spunlace material can provide a growth scaffold for cell growth and is conducive to the circulation of nutrients necessary for cell growth, it has the effect of promoting cell proliferation.

[0056] Moreover, all selenium-containing materials did not lead to a decrease in cell viability, indicating that the chitosan spunlace material loaded with nano-selenium in situ has no cytotoxicity and has good antibacterial effect and biocompatibility.

[0057] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing an antibacterial chitosan-based nonwoven medical material, characterized in that: The specific steps include: S1 pretreatment: dehydrating the chitosan spunlace substrate to remove moisture; S2 initial reaction: adding the reactant solution to the pretreated chitosan spunlace substrate, soaking it fully and then taking it out; S3 In-situ generation of nanoparticles: a reducing agent is mixed into the removed chitosan spunlace substrate, the reaction mixture is adjusted to an alkaline state, and the reducing agent reduces the reactants on the surface of the chitosan to generate antibacterial nanoparticles in situ; S4 Preparation of antibacterial material: After washing the material treated in step S3, excess liquid in the material is removed to obtain an antibacterial chitosan-based nonwoven medical material.

2. The method for preparing the antibacterial chitosan-based nonwoven medical material according to claim 1, characterized in that: The specific steps of S1 are: dehydrating the chitosan spunlace substrate at a certain temperature for 6 hours to remove excess water in the material.

3. The method for preparing the antibacterial chitosan-based nonwoven medical material according to claim 1, characterized in that: In S2, Na2SeO3 solution is added to a container containing chitosan spunlace substrate, and the solution is taken out after swelling for 2 hours under constant temperature oscillation conditions.

4. The method for preparing the antibacterial chitosan-based nonwoven medical material according to claim 1, characterized in that: The specific steps of S3 are as follows: adding a reducing agent solution and a NaOH solution to the soaked chitosan spunlace substrate, adjusting the reaction mixture to an alkaline state, and reducing it under constant temperature oscillation conditions for 1 hour.

5. The method for preparing the antibacterial chitosan-based nonwoven medical material according to claim 1, characterized in that: The reducing agent is reduced glutathione.

6. The method for preparing the antibacterial chitosan-based nonwoven medical material according to claim 5, characterized in that: In S2, the reactant solution is a sodium selenite solution, and the concentration of the sodium selenite solution is 0.5 mmol / L, 3.125 mmol / L, 5 mmol, 12.5 mmol / L or 50 mmol / L.

7. The method for preparing the antibacterial chitosan-based nonwoven medical material according to claim 6, characterized in that: The molar ratio of the added amount of sodium selenite to reduced glutathione is 1-100:

15.

8. The method for preparing the antibacterial chitosan-based nonwoven medical material according to claim 6, characterized in that: The concentration of the reducing agent solution is 0.1 mol / L, and the concentration of the NaOH solution is 3 mol / L.

9. An antibacterial chitosan-based nonwoven medical material, characterized in that: The method is prepared by any of claims 1 to 8.

10. The antibacterial chitosan-based nonwoven medical material according to claim 9, characterized in that: The invention comprises nano-selenium particles and a chitosan spunlace substrate. The nano-selenium particles are in-situ generated by sodium selenite and reduced glutathione on the surface of the chitosan spunlace substrate.

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