Polysaccharide-based hydrogel mask loaded with Pickering emulsion for high-efficiency encapsulation and sustained release of camellia oleifera oil

Camellia oleifera oil (CO) emulsified by cationic cellulose nanofibrils. • Dual stabilization of CO via emulsion interface and gel network. • High-efficiency encapsulation and sustained release of CO by composite system. • Hydrogel retains strong antioxidant activity after 35 days of storage. In recent years, the skincare concept of nourishing skin with oils has attracted extensive attention. Camellia oleifera oil (CO) is a natural woody skincare oil with both skin barrier repair and antioxidant properties. To overcome the instability of its bioactive components, this study adopts a gel matrix composed of polyvinyl alcohol (PVA), tremella fuciformis polysaccharide (TFP) and polydopamine (PDA), loaded with CO Pickering emulsions stabilized by cationic cellulose nanofibrils (CCNF). By combining the oil-in-water emulsification method with a cyclic freeze-thaw strategy, a dual-stabilization structure of emulsion encapsulation and hydrogel network was constructed. The resultant hydrogel integrates excellent dynamic adhesion and mechanical properties, with a water holding capacity of 93.21% and a CO encapsulation efficiency of 80.38%. It enables long-term sustained release of CO for 120 h, and the release behavior follows the Fickian diffusion mechanism. It achieves DPPH and ABTS free radical scavenging ratio of 88.1% and 97.14%, respectively, with no significant attenuation of antioxidant activity during the 35 days storage period. The hydrogel also possesses favorable bacteriostatic activity and biocompatibility, with a hemolysis ratio below 5%, no skin irritation and no in vivo toxicity. This study provides a novel approach for the protection and delivery of CO as well as the green design of skincare hydrogels. Download: Download high-res image (196KB) Download: Download full-size image