A bacteriostatic and hemostatic medical dressing based on PEG modified keratin/carboxymethyl chitosan

Abstract

Maintaining a moist wound environment facilitates the wound healing process. However, traditional dressings such as medical gauze are difficult to meet this condition and easy to cause wound infection when the gauze is replaced. In this paper, a novel multifunctional medical dressing based on keratin porous materials was prepared by the freeze-drying method. Keratin was first modified by poly (ethylene glycol) dimethacrylate (PEGDMA) to increase its hydrophilicity. Then, the carboxymethyl chitosan (CMCS) was mixed with keratin solution to further improve the pore-forming properties, and finally, the solution was dried through the freezing method to obtain the porous dressing. The performance of the dressing was detailed and studied using DPPH free radical scavenging ability, water retention, blood coagulation, and bacteriostasis tests. The results showed that PEGDMA grafting greatly improved moisture retention from 22 to 43. CMCS blending not only improved the uniform and compact of the pore structure, but also effectively improved blood coagulation and antibacterial properties. After blending with CMCS, the performance of the keratin porous material was greatly improved. Carboxymethyl chitosan is positively charged, which makes the negatively charged platelets easy to aggregate, so the coagulation performance is greatly improved, and the BCI decreased to 15%. At the same time, the antibacterial performance against Staphylococcus aureus was greatly improved, and the optimal condition was PEG-g-KR:CMCS = 6:4. The PEG-g-KR/CMCS dressing prepared in this method had the characteristics of promoting wound healing, good moisture absorption and water retention, excellent blood coagulation performance and strong bacteriostasis. It is of great significance to the research and application of composite dressings.