Ultrasonic cavitation-driven construction of hydroxypropyl-β-cyclodextrin and whey protein co-assembled...

In this study, nanoparticles were prepared by self-assembly of hydroxypropyl-β-cyclodextrin (HP-β-CD) and whey protein (WP) for encapsulation and delivery of epigallocatechin gallate (EGCG), aiming to enhance its gastrointestinal stability. Two ultrasonic strategies (ultrasonic cleaning and ultrasonic cell disruption) were applied to optimize nanoparticle performance. Hydrogen bonding and hydrophobic interactions were identified as the primary driving forces for nanoparticles (CD/WP/EGCG) formation. Ultrasonic cell disruption significantly improved nanoparticle characteristics, achieving 92.65 % encapsulation efficiency and 11.94 % loading capacity, while also enhancing redispersibility and EGCG photothermal stability. After 7 days of storage, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities remained above 80 %. In vitro digestion confirmed sustained EGCG release and reduced gastric degradation (<20 %). Overall, ultrasound-assisted assembly significantly improved the physicochemical stability, antioxidant activity, and gastrointestinal digestion behavior of CD/WP/EGCG nanoparticles through cavitation and shear effects. This study proposed a protein-polysaccharide-based nanocarrier to improve the stability and bioavailability of polyphenols.