Multifunctional hemostatic polysaccharide-based sponge enhanced by tunicate cellulose: A promising approach for photothermal antibacterial activity and accelerated wound healing

Fast and effective hemostasis and protection against wound infection play a crucial role in trauma care. In this study, a sponge scaffold with a self-expanding interpenetrating macropore structure was designed via two-step cross-linking method for hemostasis and photothermal antimicrobial activity. Oxidized Konjac glucomannan (OKGM) and chitosan (CS) were crosslinked once to form a dynamic covalent bonding network, and a basic three-dimensional fiber porous network framework was constructed by uniformly dispersing Tunicate nano-cellulose (TCNCs). Secondary crosslinking introduced Polydopamine (PDA NPs) into the sponge, while dynamic hydrogen bonds were interleaved to stabilize the frame. PDA NPs enhanced the sponge's antibacterial and antioxidant properties due to its good photothermal conversion efficiency and oxygen radical scavenging ability. Compared to cotton gauze and gelatin sponges, the composite sponges showed superior blood cell adhesion and platelet activation. In tests on rat liver trauma models, composite sponges showed shorter hemostasis time (12 +/- 2.17 s) and less blood loss (0.1 +/- 0.052 g). Sponges can protect wound tissue through their adhesion properties. In the full-thickness wound model infected with S. aureus, the composite sponge accelerated wound healing. Overall, this composite sponge has great potential for clinical use as a wound dressing.