Foam dressing incorporating herbal extract: An all-natural dressing for potential use in wound healing

Abstract

Silk fibroin protein, gastrodia elata, and tea tree oil are naturally derived and have been used throughout human history. This work develops an all-natural and highly porous foam-containing silk fibroin protein and above herbal extract, as a dressing for wound management. Scanning electron microscopic analyses and measurements of porosity by Archimedes method revealed a highly porous structure with porosity ranging from 40%–80%, depending on the preparation condition. In vitro, cytotoxicity test of a series of gastrodia elata–containing silk fibroin protein and tea tree oil–containing silk fibroin protein foam dressings on 3T3 fibroblast cells showed 90%–100% cell viability, which indicated that the produced all-natural dressings have no significant cytotoxicity toward skin cells. In another anti-inflammatory assay using the lipopolysaccharide-induced inflammatory Raw 264.7 macrophages model, the produced two dressings exhibited up to 70% and 90.1% of reduction in the formation of nitrite, in comparison with the untreated group. In vivo studies showed that all herbal extract–containing foam dressings accelerated wound recovery and achieved full closure of the wound within 21 days, and the histological analysis of regenerative skin tissues indicated that the produced foam dressings enhance the generation of thicker, denser, and more abundant collagen fibers in the dermis layer in comparison with the positive and negative control groups.