Encapsulation and Sustained Release of Quercetin-Loaded pH-Responsive Intelligent Nanovehicles Based on the Coassembly of Pea Protein Isolate and Hyaluronic Acid

A pea protein isolate (PPI)-hyaluronic acid (HA) nanocarrier delivery system was created for quercetin (Que) encapsulation using the pH conversion strategy. The self-assembly of the PPI-HA binary nanocomplex (HPP) were mainly driven by electrostatic and hydrophobic interactions. Que was successfully encapsulated in HPP nanocomposites (Que@HPP), which exhibited preferable redispersibility, and encapsulation efficiency (87.51%), loading capacity (14.50%). Que@HPP provided superior resistance to external environmental stresses (pH, ionic strength, high temperature, light exposure, and long-term storage), while maintaining its primary antioxidant activity after 15 days. Compared to free Que, the encapsulated Que shifted from a crystalline to an amorphous form, diffusing more easily through nanoparticle pores. Moreover, the encapsulated Que (Que@HPP) were stable in simulated gastric fluid (SGF, pH = 1.2) and released slowly in simulated intestinal fluid (SIF, pH = 6.8) compared to naked Que, demonstrating its potential to respond to specific external pH environments. Thus, the fabrication of HPP nanovehicles for Que encapsulation is a viable solution to improve its stability and release behaviors.