阅读说明：本技术 一种抗菌活性敷料及其制备方法 (Antibacterial active dressing and preparation method thereof ) 是由 蓝咏 刘玉 何灼华 冯龙宝 于 2020-05-07 设计创作，主要内容包括：本发明涉及一种抗菌活性敷料,所述敷料包括如下质量百分比的组分：羧甲基纤维素钠1％～4％、丝胶蛋白0.2％～2％、含克林霉素的羧甲基纤维素微球0.01％～0.2％、余量为去离子水。本发明将克林霉素负载到羧甲基纤维素微球(CMs)上得到粒径均匀的羧甲基纤维素微球(CMs@CLDM),以开发协同有效的抗菌微球,从而在不降低抗菌性能的情况下使抗生素的加入量减少,同时增加了材料的生物相容性；而且基于丝胶蛋白/羧甲基纤维素敷料,能提高单纯羧甲基纤维素敷料易降解的性能,丝胶蛋白的加入提高了CMC敷料的水稳定性和细胞粘附性能。(The invention relates to an antibacterial active dressing which comprises the following components in percentage by mass: 1 to 4 percent of sodium carboxymethylcellulose, 0.2 to 2 percent of sericin, 0.01 to 0.2 percent of carboxymethyl cellulose microsphere containing clindamycin and the balance of deionized water. According to the invention, clindamycin is loaded on carboxymethyl Cellulose Microspheres (CMs) to obtain carboxymethyl cellulose microspheres (CMs @ CLDM) with uniform particle size, so as to develop synergistically effective antibacterial microspheres, thereby reducing the addition of antibiotics without reducing antibacterial performance and simultaneously increasing the biocompatibility of the material; and based on the sericin/carboxymethyl cellulose dressing, the easy-degradation performance of the single carboxymethyl cellulose dressing can be improved, and the water stability and the cell adhesion performance of the CMC dressing are improved by adding the sericin.)

1. The dressing with the antibacterial activity is characterized by comprising the following components in percentage by mass: 1 to 4 percent of sodium carboxymethylcellulose, 0.2 to 2 percent of sericin, 0.01 to 0.2 percent of carboxymethyl cellulose microsphere containing clindamycin and the balance of deionized water.

2. The dressing of claim 1, wherein the dressing comprises the following components in percentage by mass: 2% of sodium carboxymethylcellulose, 1% of sericin, 0.1% of carboxymethyl cellulose microspheres containing clindamycin and the balance of deionized water.

3. The dressing of claim 1 or 2, wherein the preparation method of the clindamycin-containing carboxymethyl cellulose microsphere comprises the following steps:

(1) adding sodium carboxymethylcellulose and clindamycin into deionized water, then adding liquid paraffin and span 80, heating in a water bath, dropwise adding a gelatin solution to form a mixed solution, adding a cross-linking agent, and stirring for reaction;

(2) and after the reaction is finished, centrifuging the reaction solution to obtain a precipitate, washing, and freeze-drying the precipitate to obtain the carboxymethyl cellulose microsphere containing the clindamycin.

4. The dressing of claim 3, wherein the mass ratio of the sodium carboxymethylcellulose to the clindamycin is (10-30): 1.

5. the dressing of claim 3, wherein the rotation speed of the stirring reaction is 400-1000 rmp, the time of the stirring reaction is 2h, the centrifugation time is 1-10 min, and the cross-linking agent is glutaraldehyde.

6. The dressing of claim 1 or 2, wherein the sericin is prepared by a method comprising: cutting silkworm cocoon into pieces, washing with deionized water, and soaking in Na₂CO₃Boiling the solution, centrifuging, filtering to remove insoluble residue, dialyzing with deionized water, and lyophilizing to obtain sericin.

7. The dressing of claim 6, wherein the boiling time is 0.5-2 h, the rotation speed of the centrifugation is 1000-5000 rpm, and the time of the centrifugation is 5-15 min.

8. A method of manufacturing a dressing according to any of claims 1 to 7, comprising the steps of: adding sodium carboxymethylcellulose and sericin into deionized water, stirring until completely dissolving, adding carboxymethyl cellulose microspheres containing clindamycin, stirring to uniformly disperse the microspheres, pouring the reaction solution into a mold, freezing overnight, drying, and crosslinking to obtain the antibacterial active dressing.

9. The method of claim 8, wherein the stirring is performed for a period of 3 hours until complete dissolution, the stirring is performed for a period of 15 minutes to uniformly disperse the microspheres, and the freezing is performed at-70 ℃ overnight.

10. The method of claim 8, wherein the temperature of the crosslinking is 70 ℃ and the time of the crosslinking is 72 hours.

Technical Field

The invention relates to an antibacterial active dressing and a preparation method thereof, belonging to the technical field of medical biomaterials.

Background

The skin plays a key role in protecting the body from external invasion. The skin, which is the first layer in contact with the surrounding environment, is the largest layer and is more vulnerable to injury. Thus, the use of effective wound dressings has been considered as an effective way to accelerate the healing process. A suitable wound dressing should be able to provide optimal conditions around the wound, which best mimic the extracellular matrix (ECM) of the skin, to help allow epithelial cell movement, properly transfer oxygen, allow a moist environment, drain wound secretions, and largely prevent wound infection.

Sodium carboxymethylcellulose (CMC) -based dressings have received particular attention in this regard due to their richness, transparency, and low cost. The high hydrophilicity of CMC leads to a high absorption of wound exudate; it also provides a moist environment around the wound and prevents tissue desiccation, which is important in burn and diabetic wounds. Despite these improvements, CMC dressings have relatively poor cell adhesion and have been reported in previous studies. In addition, the lower antimicrobial activity and water stability limit their practical applicability as wound dressings. To compensate for this drawback, the mixing of CMC with other polymers is a viable solution. In addition to selecting CMC, selecting a naturally based protein may be closer to making a structure similar to natural ECM when making a dressing.

Sericin is a natural biomaterial derived from silk, and has excellent biocompatibility, low immunogenicity, natural cell adhesion, proliferation promoting effect and adjustable mechanical properties. Previous studies have demonstrated that sericin or a sericin derivative does not stimulate inflammatory responses in vitro and in vivo. In addition, the sericin has the advantages of simple preparation, low cost, convenient storage and long shelf life. Sericin-coated substrate L929 fibroblasts had better attachment and growth than collagen-coated substrate, sericin extracted from silkworm cocoon was more effective in healing wound because epithelial cells were almost completely regenerated.

The chitosan microsphere is a drug carrier material with wide application. However, chitosan has poor water solubility, and hydrochloric acid or acetic acid is added to increase the solubility during dissolution, and the acids are difficult to completely remove during cleaning and have certain irritation to cells. Compared with chitosan, the water solubility of sodium carboxymethylcellulose is greatly improved, so that the application range of the chitosan is expanded, and the characteristics of biocompatibility and the like of the chitosan are maintained.

Clindamycin is a potent antibiotic used to treat severe skin and soft tissue infections, particularly infections caused by staphylococcus aureus (s.

Aiming at the problem that the traditional antibiotic dressing dose can generate drug resistance greatly, the invention loads clindamycin on carboxymethyl Cellulose Microspheres (CMs) so as to improve antibacterial performance and biocompatibility and ensure that the dressing is suitable for healing skin wound surfaces. Also, in the preparation of dressings, the selection of a naturally based protein (sericin) may more closely resemble the structure of a natural cytoplasmic matrix, in addition to the selection of pure sodium carboxymethyl cellulose. The system is fully expandable to any other soluble drug, thereby achieving the effect of slow release of the drug in the dressing.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide an antibacterial active dressing and a preparation method thereof.

In order to achieve the purpose, the invention adopts the technical scheme that: an antibacterial active dressing comprises the following components in percentage by mass: 1 to 4 percent of sodium carboxymethylcellulose, 0.2 to 2 percent of sericin, 0.01 to 0.2 percent of carboxymethyl cellulose microsphere containing clindamycin and the balance of deionized water.

As a preferred embodiment of the dressing of the present invention, the dressing comprises the following components by mass: 2% of sodium carboxymethylcellulose, 1% of sericin, 0.1% of carboxymethyl cellulose microspheres containing clindamycin and the balance of deionized water.

As a preferred embodiment of the dressing of the present invention, the preparation method of the carboxymethyl cellulose microsphere containing clindamycin comprises:

(1) adding sodium carboxymethylcellulose and clindamycin into deionized water, then adding liquid paraffin and span 80, heating in a water bath, dropwise adding a gelatin solution to form a mixed solution, adding a cross-linking agent, and stirring for reaction;

(2) and after the reaction is finished, centrifuging the reaction solution to obtain a precipitate, washing, and freeze-drying the precipitate to obtain the carboxymethyl cellulose microsphere containing the clindamycin.

As a preferred embodiment of the dressing, the mass ratio of the sodium carboxymethyl cellulose to the clindamycin is (10-30): 1. preferably 20: 1.

As a preferred embodiment of the dressing, the rotation speed of the stirring reaction is 400-1000 rmp, the time of the stirring reaction is 2 hours, the centrifugation time is 1-10 min, and the cross-linking agent is glutaraldehyde. Preferably, the rotation speed of the stirring reaction is 600rmp and the centrifugation time is 3 min.

As a preferred embodiment of the dressing of the present invention, the preparation method of the clindamycin-containing carboxymethyl cellulose microsphere (CMs @ CLDM) comprises the following steps:

(1) weighing 0.3g of sodium carboxymethylcellulose and 0.03g of clindamycin, dissolving in 10mL of deionized water, then adding 10mL of liquid paraffin, adding magnetons, stirring, then adding 2mL of span 80 serving as an emulsifier, and heating in a water bath at 40 ℃;

(2) transferring 10mL of 3% prepared gelatin solution into a dropping funnel, and slowly dropping the gelatin solution into the reaction solution at the rotating speed of 400rmp until the dropping is finished (about 4h) to obtain a mixed solution;

(3) then adding 0.2mL of 5 wt% glutaraldehyde (20 uL each time and once every 20 minutes) as a cross-linking agent, keeping the rotating speed of 400rmp, and continuing stirring for reaction for 2 hours;

(4) centrifuging the reaction solution at the rotating speed of 4000rmp for 3min to obtain a precipitate, alternately washing the precipitate with isopropanol and absolute ethyl alcohol for 3 times, and freeze-drying the washed precipitate to obtain the carboxymethyl cellulose microsphere (CMs @ CLDM) containing clindamycin.

As a preferred embodiment of the dressing, the preparation method of the sericin comprises the following steps: cutting silkworm cocoon into pieces, washing with deionized water, and soaking in Na₂CO₃Boiling the solution, centrifuging, filtering to remove insoluble residue, dialyzing with deionized water, and lyophilizing to obtain sericin.

In a preferred embodiment of the dressing of the present invention, the boiling time is 0.5 to 2 hours, the rotation speed of the centrifugation is 1000 to 5000rpm, and the time of the centrifugation is 5 to 15 min. Preferably, the boiling time is 1h, the rotation speed of the centrifugation is 3500rpm, and the centrifugation time is 10 min.

As a preferred embodiment of the dressing of the present invention, the preparation method of sericin (Ser) comprises: extracting sericin from Bombyx Bombycis by hot and alkaline degumming, cutting 5.0g Bombyx Bombycis into pieces, washing with deionized water, soaking in 200mL of 0.02MNa₂CO₃Boiling the solution for 1 hour, then removing insoluble residues by centrifugation (3500rpm, 10 minutes) and filtration, dialyzing the reaction solution (MWCO 3.5kDa) against deionized water to remove Na₂CO₃Dialyzing for 2 days, and freeze-drying to obtain sericin.

In a second aspect, the present invention provides a method for preparing the dressing, comprising the steps of: adding sodium carboxymethylcellulose and sericin into deionized water, stirring until completely dissolving, adding carboxymethyl cellulose microspheres containing clindamycin, stirring to uniformly disperse the microspheres, pouring the reaction solution into a mold, freezing overnight, drying, and crosslinking to obtain the antibacterial active dressing.

As a preferable embodiment of the preparation method of the present invention, the time for stirring until complete dissolution is 3 hours, the time for stirring to uniformly disperse the microspheres is 15 minutes, and the temperature for freezing overnight is-70 ℃.

As a preferred embodiment of the preparation method of the invention, the temperature of the cross-linking is 70 ℃, and the time of the cross-linking is 72 h.

Compared with the prior art, the invention has the beneficial effects that:

(1) the invention takes sericin, sodium carboxymethylcellulose and carboxymethyl cellulose microspheres loaded by clindamycin as raw materials, prepares the three-dimensional antibacterial wound dressing with obviously interconnected porous structures by freeze drying, simulates an extracellular matrix structure, and has good mechanical properties and biocompatibility.

(2) According to the invention, clindamycin is loaded on carboxymethyl Cellulose Microspheres (CMs) to obtain carboxymethyl cellulose microspheres (CMs @ CLDM) with uniform particle size, so as to develop synergistically effective antibacterial microspheres, thereby reducing the addition of antibiotics without reducing antibacterial performance and simultaneously increasing the biocompatibility of the material; and based on the sericin/carboxymethyl cellulose dressing, the easy-degradation performance of the single carboxymethyl cellulose dressing can be improved, and the water stability and the cell adhesion performance of the CMC dressing are improved by adding the sericin.

(3) Aiming at the problem that the traditional antibiotic dressing dose can generate drug resistance greatly, clindamycin is loaded on carboxymethyl Cellulose Microspheres (CMs), so that the antibacterial performance and the biocompatibility can be improved, and the dressing is suitable for healing skin wound surfaces. The clindamycin releasing time of the composite dressing can reach 14 days, and the composite dressing has a good antibacterial effect on staphylococcus aureus and escherichia coli. Compared with the traditional dressing containing antibiotics, the carboxymethyl cellulose microsphere dressing loaded with clindamycin has very high bactericidal performance.

Drawings

FIG. 1 is an external view of dressings prepared in example 5 and comparative example 2; in which the left side is an appearance view of the dressing prepared in comparative example 2 and the right side is an appearance view of the dressing prepared in example 5.

FIG. 2 is a scanning electron micrograph of the dressings prepared in example 5 and comparative example 2; wherein, A is the scanning electron microscope image of the dressing prepared in comparative example 2, and B is the scanning electron microscope image of the dressing prepared in example 5.

Fig. 3 is a graph of the release profile of clindamycin from the dressings prepared in example 5 and comparative example 2.

FIG. 4 is a statistical graph of cell viability for the dressings prepared in examples 4-6 and comparative examples 1-2.

Detailed Description

To better illustrate the objects, aspects and advantages of the present invention, the present invention will be further described with reference to the accompanying drawings and specific embodiments.