新型纳米银基抗感染敷料的研制及生物学效应评价

Preparation and biological evaluation of nano silver based wound dressing with antibacterial activity

目的研制具有优良抗菌性能的纳米银抗感染敷料,探索其组成对抗菌活性及创面愈合的调控作用。方法利用化学交联和冷冻干燥技术制备葡聚糖修饰纳米银(DAgNPs)/壳聚糖-明胶(SCG)抗感染敷料,体外评价其对革兰阴性大肠杆菌(E.coli)和革兰阳性金黄色葡萄球菌(S.aureus)的抑制作用,体内用SD大鼠全层创伤感染模型进行临床预先研究。在伤口愈合的过程中采用SCG创伤敷料并且进行伤口愈合的观察、血流灌注和组织学染色分析。结果 SCG敷料的孔隙率高达87%。与CG敷料相比,SCG敷料能更加明显地抑制E.coli和S.aureus的活性。与商用敷料和纱布相比,SCG敷料可显著减少伤口感染,促进表皮和真皮的再生。此外,DAgNPs还能缩短创面愈合时间。结论 SCG敷料在感染性伤口愈合中具有潜在的应用前景。

Objective To prepare the nano silver based wound dressing with excellent antibacterial activity and evaluate its potential in wound healing. Methods A novel chitosan-gelatin（ CG） based antibacterial wound dressing with the incorporation of dextran-silver nanoparticles（ DAg NPs） was prepared via chemical crosslinking and lyophilization technology. The antibacterial activity of the DAg NPs / chitosan-gelatin（ SCG） was investigated using Gram-negative Escherichia coli（ E. coli） and Gram-positive Staphylococcus aureus（ S. aureus）. A pre-clinical study was performed using the full-thickness infected wound model in Sprague-Dawley rats. The progress of wound-healing using the SCG wound dressing was monitored by wound closure observation,blood perfusion analysis and histology staining. Results The SCG sponge had high porosity（ more than 87%）. Compared with CG sponge,the SCG sponge showed considerable antibacterial activity against both E. coli and S. aureus. Compared with commercial dressing and gauzes,the SCG sponge could significantly reduce the infection of wound and improve the regeneration of epidermis and dermis. Moreover,the addition of DAg NPs could shorten the wound healing time. Conclusion The SCG sponge dressing will be a promising candidate in the treatment of wounds.