Alginate/chitosan-coated zein nanoparticles for the delivery of resveratrol

The aim of this study was to evaluate the effect of alginate/chitosan complex coating on the delivery of resveratrol encapsulated in zein particles. Resveratrol-loaded zein (RZ) particles had a particle size of ∼72 nm, ζ-potential of +15.01 mV and encapsulation efficiency >70%. RZ particles were coated with alginate/chitosan (Alg/Chi) complex layer at various polysaccharide concentrations. RZ-Alg/Chi spherical particles had the smallest size of 160.9 nm and ζ-potential of +43.01 mV at the concentration of either polysaccharide being 0.02%. FTIR and XRD results confirmed a change in the physical state of resveratrol from crystalline to amorphous and formation of the alginate/chitosan complexes. The Alg/Chi coating did not affect encapsulation efficiency of resveratrol but did improve the photostability, sustained release and bioaccessibility of resveratrol. Released resveratrol decreased to 31% after gastric digestion, while the polyphenol bioaccessibility increased to 81%. Therefore, zein-alginate/chitosan particles could be the potential delivery system for polyphenols.