The Preparation Of Antibiotic Composite Silk Fibroin Scaffold And Its Therapeutic Efficacy In Infected Full-thickness Burns

Despite advances in burn treatment, burn infection remains a major cause ofmorbidity and mortality. In this study, an antibacterial silk fibroin (SF) scaffold forburn treatment was designed.To achieve this, gelatin microspheres (GMs) wereimpregnated with the antibiotic Vancomycin（Vm）or gentamycin sulphate (GS), andthe antibiotic-impregnated GMs were then embedded in a SF matrix to fabricateantibiotic/GMs/SF scaffolds by a freeze-drying step.Some physical and antimicrobial properties of the prepared composite scaffoldswere investigated and the results demonstrated that the average pore size and porosityof the composite scaffold were60–80μm and75%, respectively. The compressivestress and compressive modulus of composite scaffold were140and468KPa,respectively. Furthermore, the drug release rate of the composite scaffolds wassignificantly slower than other scaffolds. In addition, the drug release rate of compositescaffold well matched with the degradation rate of SF scaffold. And the composite scaffoldexhibited stronger antimicrobial activities against Escherichia coli (E. coli),Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa).Hence, we evaluated the wound-healing effects and antibacterial properties of theGS/GMs/SF scaffolds in a rat full-thickness burn infection model. During21days, theGS/GMs/SF scaffolds not only significantly reduced burn infection by P. aeruginosabut also accelerated the regeneration of the dermis and exhibited higherepithelialisation rates than did other scaffolds.Thus, composite scaffolds are potentially effective for treatment offull-thickness infected burns, and are a promising therapeutic tool for severely burnedpatients.