Local delivery of linezolid via chitosan-gelatin hydrogel coated orthopedic implants as a promising strategy for treatment of implant-associated infections.

Implant-related infections are a serious complication caused by the colonization of bacteria on the surface of surgical implants. These infections can reduce the durability of implants and lead to additional surgeries to replace them. Local antibiotic therapy has received increasing attention for preventing and treating infections related to implants. The purpose of this study was to develop a biocompatible and crosslinker-free chitosan-gelation hydrogel impregnated with linezolid (CS-Gel-LZD) as a promising local delivery system for combating implant-associated infections. The resulting hydrogel exhibited potent antibacterial activity, excellent biodegradability and high cytocompatibility and hemocompatibility. The hydrogel also provided a prolonged releasing profile for LZD, approximately 4 days. In the in vivo study, CS-Gel-LZD displayed significantly higher clearance of bacteria than CS-Gel hydrogel without LZD in infected bone and surrounding tissues. Furthermore, radiographic imaging and pathology analysis exhibited no signs of infections in the CS-Gel-LZD treated group. According to these findings, incorporation of LZD in the CS-Gel hydrogel could be a promising platform for preventing and treating implant-associated infections.