Nanoparticles for Synergistic Delivery of Curcumin and Quercetin Based on Zein and Sodium Caseinate: Preparation, Characterization, and Intestinal Absorption

The purpose of the study was to characterize the basic structure of nanoparticles (Zein-CS-Cur-Que) embedded in curcumin and quercetin, realize the synergistic antioxidant of dietary polyphenols, and improve the transmembrane transport rate and bioavailability of curcumin. The oral delivery system Zein-CS-Cur-Que developed based on the synergistic encapsulation of curcumin and quercetin using the anti-solvent method with corn alkyd-soluble proteins and sodium caseinate possessed varying nanoparticle sizes (173.96-191.03 nm) and good dispersibility (PDI < 0.17), and relied on electrostatic interactions, hydrogen bonding, and hydrophobic interactions to successfully encapsulate curcumin (94.62%) and quercetin (73.75%). The results showed that Zein-CS-Cur-Que enhanced the stability and antioxidant activity of curcumin, and increased the bioaccessibility (nearly 2-fold) and rate of translocation (nearly 2-fold) of curcumin in the gastrointestinal tract significantly. Therefore, the nanocomposite system developed in this study is crucial for the development of functional foods and dietary supplements, providing effective insights into the synergy of polyphenol interactions.