Preparation of elemental tellurium nanoparticles - sucrose sol and its antioxidant activity in vitro

The elemental tellurium nanoparticles (TeNPs) - sucrose sol was prepared by the reaction of sodium tellurite with ascorbic acid in sucrose aqueous solution. The results indicated that TeNPs were dispersion excellent in the TeNPs - sucrose sol and the morphology of TeNPs was needle-like with about 70 nm in width and 500 nm in length. The antioxidant activity of the TeNPs - sucrose sol in vitro was estimated by pyrogallol autoxidation method, Fenton method and oxygen radical absorbance capacity (ORAC) assay. The results showed that a certain amount of TeNPs - sucrose sol could effectively scavenge superoxide anion free radical and hydroxyl free radical with scavenging rates of 73 % and 57 %, respectively. ORAC assay was used to measure the total antioxidant capacity of TeNPs - sucrose sol. The order of ORAC values was 2.25 mu mol center dot L-1 TeNPs - 0.025 % sucrose sol > 0.025 % sucrose > 2.25 mu mol center dot L-1 Na2TeO3 > 1.63 mu mol center dot L-1 ascorbic acid. The results suggested that the TeNPs - sucrose sol had the excellent antioxidant activity and TeNPs were the dominating contributors to antioxidant capacity of the TeNPs - sucrose sol.