Zein/Hyaluronic Acid/Propylene Glycol Alginate Nanoparticle-Stabilized Pickering Emulsion for the Encapsulation of Astaxanthin as a Delivery System.

Astaxanthin exhibits significant antioxidant and cardioprotective properties. However, its photodegradability and thermal sensitivity challenge its application. Zein/hyaluronic acid/propylene glycol alginate (zein/HA/PGA) nanoparticles were fabricated using a pH cycling method. The nanoparticles exhibited a contact angle of 89.20 ± 0.32°, indicating favorable amphiphilic characteristics. Fourier-transform infrared spectroscopy revealed intermolecular interactions among zein, HA, and PGA, consistent with hydrogen bonding and electrostatic attractions. Molecular docking results clarified the binding stability of zein with HA. The zein/HA/PGA nanoparticles at a concentration of 2.4 % (w/v) and an oil phase volume fraction of 0.6 facilitated the formation of Pickering emulsions with high stability and robust ionic strength tolerance (up to 500 mM NaCl). Rheological assessments demonstrated a higher interfacial tension and dilatational elasticity. Astaxanthin was encapsulated by Pickering emulsion, and gastrointestinal release simulations showed a bioavailability of 17.57 ± 0.34%. The zein/HA/PGA nanoparticle-stabilized Pickering emulsions offer a promising platform for applications in nutraceuticals and cosmeceuticals. PRACTICAL APPLICATIONS: This study provides a novel strategy for the preparation of Pickering emulsions utilizing food-grade nanoparticles as stabilizers and expands the scope of applications within the food, cosmetic, and pharmaceutical sectors. Furthermore, the natural encapsulated astaxanthin has a potential to be used as a functional ingredient as the release properties in gastrointestinal conditions.