Amphipathic medical composite cotton gauze with unidirectional drainage and anti-adhesion properties for wound healing

Abstract

Medical gauze is the most commonly used dressing in wound treatment. However, the issues of wound margin infiltrated with exudate and tissue adhesion pose severe challenges to the application of gauze. Therefore, studying medical gauze with unidirectional drainage function and anti-adhesion ability is imperative. In this study, nano silica (SiO₂) sol was used as a modifier to modify the surface of cotton gauze, and hexadecyltrimethoxysilane (HDTMS) was used for low-surface-energy modification to improve the hydrophobicity of gauze. Based on the Janus wettability theory, a multifunctional amphipathic medical composite gauze was prepared by combining hydrophobic cotton gauze with hydrophilic cotton gauze to promote wound healing. The top hydrophilic cotton gauze functioned as an absorption layer, which could directionally transfer the wound exudate away from the wound site, thereby providing a drier condition to reduce the risk of wound infection. The hydrophobically modified cotton gauze in contact with the wound site had an excellent anti-adhesion effect on proteins in exudate to prevent secondary damage caused by dressing change. In addition, we also studied the influence of the surface modification method, contact layer structure, and absorption layer structure on the properties of the gauze, and evaluated the biocompatibility and comfort of the optimized composite gauze, providing an experimental basis for the market promotion and application of functional medical cotton gauze. This study showed that in-situ growth after surface incorporation of SiO₂ particles was the ideal modification method for cotton gauze. The optimized composite gauze had excellent unidirectional drainage function (the unidirectional transmission index difference was above 1400) and anti-adhesion effect (the peel energy was 68.30% lower than that of the control group), no cytotoxicity, and good comfort.