A potential antibacterial wound dressing of cefadroxil chitosan nanoparticles in situ gel: Fabrication, in vitro optimization and in vivo evaluation

Wound healing following skin injury is a natural phenomenon that usually lacks quality, rapidity, and aesthetics. Thus, the purpose of this study was to fabricate a new easily applied in situ gel of cefadroxil (CDX) loaded chitosan nanoparticles (CDX-CSNPs) that could promote wound healing, capable of inhibiting the possible accompanying bacterial infection. The nanoparticles were prepared by double emulsion technique and the influence of formulation parameters on drug entrapment efficiency (EE%), particle size (PS), polydispersity index (PDI) and zeta potential (ZP) were investigated using a full factorial design. The results show that the optimized CDX-CSNP1 composed of low molecular weight chitosan (0.2%w/v) was spherical with EE%, PS, PDI and ZP of 84.25 +/- 0.02, 408.30 +/- 53.17 nm, 0.458 +/- 0.048 and 22.80 +/- 0.57 mV, respectively. DSC and XRD studies confirmed the amorphous nature of the drug. After ensuring the safety and non toxicity of CDX-CSNP1 in situ gel through cytotoxic study, the antibacterial activity was evaluated using a rat skin infection model against Staphylococcus aureus. Compared to the rats treated with free CDX, the CDX-CSNP1 treated group revealed a remarkable accelerated wound healing process and bacterial clearance which was further confirmed by the histopathological examination of skin biopsies.