Zein-whey protein isolate-carboxymethyl cellulose complex as carrier of apigenin via pH-driven method: Fabrication, characterization, stability, and in vitro release property

The poor water solubility of apigenin limits its application feasibility in food and medicine. To address this issue, this study successfully prepared apigenin-loaded zein composite nanoparticles using the pH-driven self-assembly method. The nanoparticles were stabilized by hydrophilic whey protein isolate and carboxymethyl cellulose. The composite nanoparticles exhibited high potential, small size, and uniform particle size distribution. Circular dichroism and fluorescence spectroscopy results revealed that the nanoparticles showed conformational changes from unfolding to folding during the neutralization process. The main driving forces for the formation of nanoparticles were hydrophobic interaction and hydrogen bonding. Encapsulation efficiency and loading capacity of apigenin were 87.28% and 8.17%, respectively. Compared with single zein, apigenin-loaded zein-whey protein isolate-carboxymethyl cellulose showed better re-dispersibility (92.83%), thermal stability, and in vitro release efficiency of apigenin (65.27%).