Constructing a hemostatic sponge loaded with copper nanoparticles and carboxymethyl chitosan for wound hemostasis and infection prevention†

Uncontrolled hemorrhage and infection pose serious risks to patient survival, highlighting the critical need for multifunctional hemostatic materials that are safe, effective, and highly biocompatible. In response to this clinical demand, we have developed a novel design strategy that rapidly achieves hemostasis and prevents infection. This research introduces a dual-network multifunctional hemostatic sponge, CMC/PDA@Cu, crafted from polysaccharide materials and specifically engineered for application at bleeding sites compromised by drug-resistant bacteria. Utilizing the natural hemostatic properties of carboxymethyl cellulose (CMC), this material facilitates swift coagulation via electrostatic interactions that enhance the adhesion and aggregation of blood cells. Concurrently, copper nanoparticles (Cu-NPs) are synthesized in situ through redox reactions with copper ions and the catechol groups in polydopamine (PDA), enabling the prolonged release of copper ions and achieving 48 hours of antibacterial activity. The synergistic photothermal properties of PDA and Cu-NPs increased the photothermal conversion efficiency to 27.5%, significantly reducing the time required for bacterial elimination from 24 hours to just 3 hours. Furthermore, copper ions serve as cationic coagulation enhancers, bolstering hemostatic efficiency. The resultant material offers a combined solution for effective hemostasis and infection management. In experimental applications using a rat liver hemorrhage model, the CMC/PDA@Cu sponge dramatically minimized blood loss to 0.02 ± 0.01 mg, marking the fastest recorded hemostasis time of 37.17 ± 3.76 seconds. In a separate rat tail amputation model, the sponge reduced the blood loss to 0.91 ± 0.47 g, with a hemostasis time of 75.01 ± 4.52 seconds. These results lay a foundational mechanistic basis for the rational design of advanced, safe, and controllable hemostatic materials, elucidating the critical structure–function relationships in terms of material composition, surface characteristics, and their impact on hemostasis, antimicrobial efficacy, and biocompatibility. This work sets the stage for the future development of next-generation hemostatic materials aligning with clinical requirements.