Chitosan/cellulose based multilayer dressing with directional exudate transport for sequential hemostasis and anti-infection in wound management

A multilayer fibrous dressing based on chitosan (CS) and wood pulp cellulose (WPC) fibers was designed, integrated with hydrophilic/hydrophobic heterogeneous polyester and superhydrophobic polytetrafluoroethylene layers, to achieve sequential functions of hemostasis, directional exudate transport, and anti-infection. The wound-facing hydrophilic/hydrophobic fiber layer creates directional microchannels which pump exudate spontaneously toward the intermediate layer. The polysaccharide composite in intermediate layer rapidly absorbs exudate, promotes hemostasis via platelet activation, and provides antibacterial activity. The outer superhydrophobic fiber layer acts as a physical bacterial barrier. Compared with gauze, the dressing reduced blood loss by 66% and shortened hemostasis time by 30%. The dressing also showed 39% reduction in rewetting rate, blocked the endotoxin back-diffusion, and achieved excellent antibacterial activity against S. aureus and E. coli, along with good biocompatibility and anti-adhesion properties. The dressings showed synergistic hemostasis, exudate management, and anti-infection functions to the time-programmed requirements of wound healing; thereby creating an optimal wound-healing microenvironment. In an infected rat model, it resulted in 92% wound closure rate by day 14, and promoted orderly collagen deposition for high-quality repair. The work demonstrates that a chitosan/cellulose-based multilayer dressing can achieve spatiotemporally sequential wound management, providing a polysaccharide-driven strategy for advanced wound care.