Preparation and Characterization of Zein/Salecan Nanocomposite Particles for Enhanced Stability and Bioactivity of Lipophilic Retinoids

Retinoids are lipophilic compounds with high biological activity but poor stability and water solubility. Herein, novel zein/salecan (Zein/Sal) nanocomposite particles were fabricated via antisolvent precipitation with polysaccharide coating and used as carriers for hydroxypinacolone retinoate (HPR). The mass ratio of zein to Sal significantly affected particle properties, with a mass ratio of 2:1 yielding a homogeneous spherical morphology and high encapsulation efficiency, while HPR was integrated in an amorphous state. The integration of zein with HPR was due to hydrogen bonding and hydrophobic interactions. The resulting HPR-loaded Zein/Sal nanocomposite particles exhibited good colloidal stability over a wide pH range, under high ionic strength conditions, and during long-term storage. Encapsulation also remarkably improved HPR stability under different temperatures and light irradiation. In vitro assays revealed that the Zein/Sal nanocomposite particles had good biocompatibility, reduced the cytotoxicity of encapsulated HPR, and promoted cellular uptake and migration with the encapsulated HPR. Steady release and improved transdermal delivery of encapsulated HPR were also achieved. These results show that Sal serves as a functional stabilizer, improving both the structural and biological functions of zein nanoparticles, and offering a viable vehicle for the delivery of lipophilic retinoids in food, pharmaceutical, and cosmetic applications.