负载万古霉素多聚乳酸-聚乙二醇-多聚乳酸抗菌温敏水凝胶的制备及性能

Preparation and performance evaluation of poly lactide-co-glycolide-b-poly ethylene glycol-b-poly lactide-co-glycolide thermosensitive antibacterial hydrogels loaded with vancomycin

目的制备缓释万古霉素的多聚乳酸-聚乙二醇-多聚乳酸(PLGA-PEG-PLGA)温敏水凝胶,探讨其理化性能、生物学性能和抗菌性能。方法PLGA(1500~2000)-PEG(1000~1500)-PLGA(1500~2000)多聚物溶液在4℃下孵育7 d,充分溶解后在37℃水浴中放置10 min成胶并负载万古霉素。冻干脱水48 h后利用扫描电镜观察其微观结构。在37℃、60 r/min条件下利用紫外-可见光谱分析绘制其体外降解曲线及药物释放曲线。以二甲基亚砜(DMSO)作为阳性对照,利用噻唑蓝(MTT)法检测本材料细胞相容性。在37℃、120 r/min条件下检测其抗菌效果。两组间比较采用独立样本t检验,多组间比较采用单因素方差分析。结果抗菌水凝胶扫描电镜结果显示,PLGA-PEG-PLGA抗菌温敏水凝胶具有疏松多孔的微观结构,载药前[(53.77±31.20)μm、后孔隙尺寸[(50.42±27.60)μm]差异无统计学意义(t=0.255,P>0.05);体外降解时长30 d;空载水凝胶组[(96.41±2.41)%]、载药水凝胶组细胞活性[(96.98±2.26)%],与DMSO组[(37.64±2.69)%]差异有统计学意义(F=1727.784,P<0.05);药物释放实验证实万古霉素可以持续释放30 d;抗菌实验结果表明,载药水凝胶可以对金葡菌提供长达72 h的抗菌效果。结论PLGA-PEG-PLGA温敏型水凝胶是一种较理想的抗生素载体,无细胞毒性,能够长效缓释负载的抗生素,具有潜在的临床应用价值。

Objective To prepare Poly lactide-co-glycolide-b-Poly ethylene glycol-b-Poly lactide-co-glycolide(PlGA-PEG-PLGA)thermosensitive hydrogel loaded with vancomycin,and to evaluate its physical and chemical characterization,biological properties and antibacterial effect.Methods PLGA(1500-2000)-PEG(1000-1500)-PLGA(1500-2000)polymer was mixed with water and incubated at 4℃for 7 days.After full dissolution,vancomycin was loaded at 37℃for 10 min.After dehydration for 48 h,the microstructure was observed by scanning electron microscope.The in vitro degradation curve and drug release curve were drawn with UV visible spectrum analysis at 37℃,60 r/min.With dimethyl surfoxide(DMSO)as the positive control,the cytocompatibility of the material was tested by methyl thiazolyl tetrazolium(MTT)kit.The antibacterial effect against S.aureus and E.coli was tested at 37℃and 120 r/min.Independent sample t-test was used to compare the mean between the two groups,and one-way ANOVA was used to compare the mean between multiple groups.The difference was statistically significant if P<0.05.Results The results of scanning electron microscopy showed that PLGA-PEG-PLGA antibacterial thermosensitive hydrogel had porous microstructure.The comparison between pore size before[(53.77±31.20)μm]and after drug loading[(50.42±27.60)μm]was not statistically significant(t=0.255,P>0.05).The degradation of this hydrogel in vitro could last to 30 days.The cell activity of empty hydrogel group[(96.41±2.41)%]and drug loaded hydrogel gel group[(96.98±2.26)%]was significantly higher than that of DMSO group[(37.64±2.69)%,F=1727.784,P<0.05].Meanwhile,the drug release curve showed that release of vancomycin sustained for 30 days.The results of antibacterial test indicated that this antibacterial hydrogel could provide antibacterial effect for up to 72 h.Conclusion PLGA-PEG-PLGA thermosensitive hydrogels hold potential as promising vancomycin sustained-release platform,which has good antibacterial effect and clinical application prospect.