Skin-Friendly Properties of the Deacetylated Konjac Glucomannan/Sodium Alginate Composite Aerogel as a Facial Mask Substrate

The skin-friendliness of aerogels has been gradually extended into the biomedical and personal care fields. The purpose of this study is to define the skin-friendly properties as three aspects, namely comfort and fit, slippage, and irritation, and to systematically evaluate the skin-friendliness of the deacetylated konjac glucomannan (KGM)/sodium alginate (D-KS) aerogel facial mask substrate. The results indicated that deacetylated KGM interacted with sodium alginate through hydrogen bonds, showing good compatibility and forming a continuous three-dimensional network structure. The deacetylation and sodium alginate optimized the microstructure of the aerogels, resulting in a low density of 72.5 mg/cm 3 and a high porosity of 98%, as well as a high shrinkage rate of 43%, which met the requirements of a facial mask. Compared with non-woven fabric, the aerogels exhibited comfortable and fitting characteristics and had the same wettability and moisture permeability. The elongation at break of the aerogel increased by 1.5 times, the compressive strain reached 60%, the slip height decreased by 68%, and the maximum peel force increased by 53.8%. Human skin tests demonstrated that the moisture content of the stratum corneum increased by 35% to 48%. In the biosafe assays, the D-KS aerogels did not cause any negative irritation on mouse cells and skin. The D-KS aerogel retained a compressive strength retention rate of 85.3%. For the loaded allantoin, the aerogels achieved sustained release, with a cumulative release rate of 88%. Summary The skin-friendly properties of biomass aerogel were defined. It showed good compatibility between D-KGM and SA based on hydrogen bonds. The D-KS aerogels exhibited comfortable and fitting characteristics. The D-KS aerogels showed good wettability and moisture permeability. The D-KS aerogels did not cause any negative irritation to the skin.