Hemorrhage remains a leading cause of early death after
trauma, and infectious complications in combat
wounds continue to challenge caregivers. Although
chitosan dressings have been developed to address these problems, they are not always effective in controlling
bleeding or killing bacteria. We aimed to refine the
chitosan dressing by incorporating a procoagulant (
polyphosphate) and an antimicrobial (
silver).
Chitosan containing different amounts and types of
polyphosphate polymers was fabricated, and their
hemostatic efficacies evaluated in vitro. The optimal
chitosan-
polyphosphate formulation (ChiPP) accelerated blood clotting (p = 0.011), increased platelet adhesion (p=0.002), generated
thrombin faster (p = 0.002), and absorbed more blood than
chitosan (p < 0.001).
Silver-loaded ChiPP exhibited significantly greater bactericidal activity than ChiPP in vitro, achieving a complete kill of Pseudomonas aeruginosa and a > 99.99% kill of Staphylococcus aureus consistently. The
silver dressing also significantly reduced mortality from 90% to 14.3% in a P. aeruginosa
wound infection model in mice. Although the dressing exerted severe cytotoxicity against cultured fibroblasts, wound healing was not inhibited. This study demonstrated for the first time, the application of
polyphosphate as a
hemostatic adjuvant, and developed a new
chitosan-based composite with potent
hemostatic and antimicrobial properties.