Caseinate vs bovine serum albumin on stabilizing zein nanoparticles for co-entrapping quercetin and curcumin

This work emphasized on the comparison of the particle characteristics and physicochemical properties of zein-caseinate and zein-BSA nanoparticles (NPs). Quercetin (Que) and curcumin (Cur) were used as the model bioactive to be co-encapsulated in the zein-caseinate and zein-BSA NPs by a combination of pH-driven and anti-solvent methods. The results demonstrated that compared with zein-caseinate, the zein-BSA exhibited smaller particle size, but stronger ability to encapsulate and retain Que and Cur during long-time storage. However, the zein-caseinate NPs showed higher thermal and ionic strength stability than zein-BSA NPs. In terms of the in-vitro bioactive release from zein-based NPs, zein-caseinate NPs appeared to show a higher Cur release rate but a lower Que release rate in comparison with zein-BSA NPs. Kinetic models revealed the Gompertz was the best fit model, indicating that the Gompertz diffusion contributed to the Que and Cur release from zein-based NPs. However, the two types of zein-based NPs showed very similar Que and Cur release profiles. These results indicated that zein-BSA and zein-caseinate composite NPs exhibited different particle characteristics and physicochemical properties in terms of encapsulation, release, and harsh environmental stability.