Durable fibrous nanohybrid sunscreen films with in-situ fabricated enteromorpha polysaccharides for enhanced UV protection.

Enteromorpha, a coastal green algae species, contains polysaccharides with excellent water solubility, biocompatibility, and antioxidant properties, making them ideal for skincare applications as natural antioxidant additives. This study introduces a modified electrospinning technique to fabricate fibrous nanohybrid sunscreen films incorporating Enteromorpha polysaccharides (EPPs) integrated with polyvinyl butyral (PVB) and titanium oxide (TiO2). The resulting film harnesses EPPs' antioxidant capabilities to protect skin from free radicals generated by TiO2 photocatalysis, while the PVB matrix and electrospun fibers provide water resistance and breathability. The nanohybrid film demonstrated remarkable photostability, maintaining its UV-blocking efficiency even after exposure to 365 nm UV radiation. Additionally, water immersion reduced its UV-blocking rate by only 2 %, confirming its strong water stability. Microscopic analysis showed no residual traces on porcine skin, effectively addressing concerns of pore-clogging and skin irritation often associated with traditional sunscreens.