Fabrication of foxtail millet prolamin/caseinate/chitosan hydrochloride composite nanoparticles using antisolvent and pH-driven methods for curcumin delivery

Co-assembled foxtail millet (FP)-sodium casein (NaCas) nanocomplex and NaCas coated FP nanoparticles (NPs) were produced by using pH-cycle and anti-solvent methods, respectively. Subsequently, the effects of chitosan hydrochloride (CHC) coating on the particle size, surface charge and physicochemical stability of the two different FP/NaCas nanoparticles (NPs) were evaluated. With the addition of CHC, the particle size of NaCas coated FP NPs and co-assembled FP-NaCas nanocomplex significantly increased from 128.3 nm and 69.5 nm to 183.5 nm and 113.8 nm, respectively. The stability of the two kinds of CHC coated FP-based NPs to different pH values and varying ionic strengths was different due to their different NP structures. Using different fabrication formulations, co-assembled FP-NaCas NPs entrapped curcumin in relatively hydrophilic microenvironment and showed higher curcumin retention rate in comparison with NaCas coated FP NPs in terms of long-term storage stability. The results revealed that the produced CHC coated FP/NaCas nanocomplexes could be very beneficial in entrapping and delivering bioactive substances.

Automated summary

This study investigated the effects of chitosan hydrochloride coating on the particle size, surface charge, and stability of foxtail millet-sodium casein nanoparticles. The results showed that the addition of chitosan hydrochloride led to an increase in particle size and improved the retention rate of curcumin in the nanoparticles.