Synthesis and characterization of chitosan/PVA/starch/ZnO/camphor and chitosan/PVA/carboxymethyl cellulose/ZnO/camphor patches for potential hemostatic application

Hemostasis is the first stage of the wound healing process activated upon injury, that results in the control of bleeding and the formation of a protective barrier. The mechanism of hemostasis includes 1) vasoconstriction, 2) the formation of a platelet plug, and 3) blood coagulation. During the hemostasis process, wound infection can exist, inhibiting epidermal maturation, and may cause bacteremia, sepsis, and multiple-organ dysfunction syndrome. In cases of severe wounds, the use of hemostatic products with antimicrobial properties is necessary to compensate for the compromised first step of wound closure. Chitosan (CS) is a naturally derived polymer that plays a leading role in the development of new hemostatic products. CS is a cationic polysaccharide with bactericidal properties; it is renewable, nontoxic, biodegradable, and hydrophilic with high reactivity, and promotes coagulation, flocculation, and biosorption. The hemostatic properties of chitosan are due to direct electrostatic interactions between negatively charged red blood cells and platelets and the positively charged CS. Researchers and pharmaceutical companies are focusing on the hemostatic properties of CS by formulating it into several hemostatic products. Ongoing research is focusing on advanced hemostatic CS-based materials with enhanced antimicrobial properties, good biocompatibility, rapid hemostatic ability, and low manufacturing cost. Hence, in this work, CS was combined with polyvinyl alcohol (PVA) and carboxymethyl cellulose or starch to prepare well-cross-linked patches with enhanced mechanical properties and blood sorption as well as immediate hemostatic properties. Additionally, ZnO and Camphor were added as natural antimicrobial agents to ensure a healthy environment, avoiding potential infections during hemostasis treatment. The successful synthesis of the fabricated CS-based patches was confirmed by FTIR, their crystallinity was researched by XRD, and water swelling was also investigated. Moreover, an investigation of the hemostatic capacity of the dressings was carried out via hemolysis and blood clotting time experiments.