Green ethanol-free antisolvent synthesis of zein–chitosan–gum arabic nanocomposites for controlled release of lupulone in topical antioxidant applications

Prolonged exposure to broadband UV radiation and oxidative stress weakens the skin’s natural protective barrier, disrupting the balance between photosensitizing and photoprotective species and accelerating visible signs of aging. Nanoparticulate delivery systems have emerged as effective tools to address skin damage through controlled release and improved bioavailability of active compounds. In this study, we developed biocompatible nanocomposites incorporating lupulone (L), a hop-derived molecule with antioxidant and antimicrobial activity, encapsulated in zein (Z) and gum arabic (GA) matrices using a green antisolvent approach based on aqueous propylene glycol. To enhance performance, chitosan (C), a hydrophilic biopolymer with complementary biological properties, was integrated into the formulation. The resulting nanocomposites demonstrated significantly improved encapsulation efficiency, sustained release of the active compound over 15 days, and enhanced antioxidant activity. The inclusion of chitosan also contributed to modulating the biological profile of the particles. These results support the potential application of the developed nanocarriers in skincare, particularly for wound healing and anti-aging formulations, while offering a safe and eco-friendly strategy for delivering sensitive bioactives such as lupulone.