Silk fibroin/chitosan/halloysite composite medical dressing with antibacterial and rapid haemostatic properties

Abstract

The problem of traumatic hemorrhage is difficult to be quickly and effectively controlled and bacterial infection is one of the major limitations in the field of biomedical dressings worldwide. This issue prolongs the time of wound healing and presents a considerable threat to safety and life of patient. In this study, medical dressings blended with silk fibroin (SF), chitosan (CS) and halloysite nanotubes (HNTs) were successfully prepared by electrospinning. The broad-spectrum antibacterial drug, chlorhexidine digluconate (CHD), was initially loaded into HNTs. Drug-loaded HNTs were dispersed into a mixture of SF and CS to prepare a micro-nanofiber dressing and its performance was examined. The results of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that the addition of HNTs had a significant effect on the micro morphology of the nanofibers. Data of thermogravimetric analysis and mechanical testing disclosed that HNTs improved the thermal stability and tensile properties of electrospun materials. Moreover, the incorporation of HNTs led to rapid coagulation of blood, as observed from the in vitro whole blood coagulation time (WBCT) experiment. In the drug release experiment, the release time of the drug was prolonged by about 8 days when drug-loaded HNTs were incorporated into electrospinning materials. Additionally, the release rate of CHD in an acidic environment was higher than that in a neutral system. In summary, the micro-nanofiber medical dressing prepared in this study presents stable mechanical strength, rapid hemostasis and antibacterial activity and has a potential for biomedical application.