Biocompatible green tea extract-stabilised zinc nanoparticles encapsulated by poly(butyl-2-cyanoacrylate) with control release profile and antioxidative capacity

Green tea extract-stabilised Zn nanoparticles (GT-Zn NPs) encapsulated by poly(butyl-2-cyanoacrylate) (PBCA@GT-Zn NPs) were developed for control release of Zn. The crucial parameters, concentrations of GT-Zn NPs and the monomer n-butyl-2-cyanoacrylate (BCA), which affected the size, polydispersity indexes (PDI) and encapsulation efficiency (EE %), were evaluated to achieve the smaller size, higher EE (%) and stably and uniformly dispersed NPs. The optimised PBCA@GT-Zn NPs with <100 nm diameter (46.38 ± 3.46 by SEM, 86.91 ± 3.66 by DLS), PDI (0.159 ± 0.042), zeta potential (−20.56 ± 2.53 mV) and EE (89.31 ± 1.09 %) were obtained. In vitro release of Zn ions was conducted at pH 7.4, showing that Zn from the self-made tablets and lyophilised PBCA@GT-Zn NPs is released significantly slower than that of GT-Zn NPs. Additionally, the PBCA@GT-Zn NP tablets are pH-responsive, non-toxic and antioxidative, suggesting that they could be used as safe food material or drug carriers, contributing to relieve Zn deficiency.