Stabilization and functionalization of selenium nanoparticles mediated by green tea and Pu-Erh tea polysaccharides

To explore a novel strategy for the combination of selenium (Se) and tea polysaccharides, monodispersed spherical nanoparticles of red amorphous elemental Se (SeNPs) of 70 nm and 35 nm in diameter with high Se content of 84 % and 86 % and significant proliferative inhibition on human carcinoma cells but low toxicity to human normal cells were prepared from the reaction between ascorbic acid and selenite using green tea and Pu-Erh tea crude polysaccharides (GTCPs and PTCPs) as templets, respectively. In particular, PTCPs showed stronger stabilizing effects compared to GTCPs according to the smaller size, and higher electrostatic stability of those SeNPs modified by PTCPs, though GTCPs exhibited more advantages in enhancing the anti-proliferative activity of SeNPs. Furthermore, tea crude polysaccharides were found a better stabilizer and functional decorator of SeNPs compared to the purified polysaccharides. This study confirmed the excellent potential of tea polysaccharides in the stabilization and functionalization of SeNPs.