Complex open musculoskeletal
wounds are a leading cause of morbidity worldwide, partially due to a high risk of bacterial contamination. Local delivery systems may be used as adjunctive
therapies to prevent
infection, but they may be nondegradable, possess inadequate
wound coverage, or migrate from the
wound site. To address this issue, a thermo-responsive,
injectable chitosan paste was fabricated by incorporating
beta-glycerophosphate. The efficacy of thermo-
paste as an adjunctive
infection prevention tool was evaluated in terms of cytocompatibility, degradation, antibacterial, injectability, and
inflammation properties. In vitro studies demonstrated thermo-
paste may be loaded with
amikacin and
vancomycin and release inhibitory levels for at least 3 days. Further, approximately 60% of thermo-
paste was enzymatically degraded within 7 days in vitro. The viability of cells exposed to thermo-
paste exceeded ISO 10993-5 standards with approximately 73% relative viability of a control
chitosan sponge. The ejection force of thermo-
paste, approximately 20 N, was lower than previously studied
paste formulations and within relevant clinical ejection force ranges. An in vivo murine biocompatibility study demonstrated that thermo-
paste induced minimal
inflammation after implantation for 7 days, similar to previously developed
chitosan pastes. Results from these preliminary preclinical studies indicate that thermo-
paste shows promise for further development as an
antibiotic delivery system for
infection prevention.