(Au)核(Ag)壳纳米微粒光度法快速检测过氧化氢

Rapid Spectrophotometric Detection of Hydrogen Peroxide Using(Au)_(core)(Ag)_(shell)Nanoparticle

以粒径为10 nm的纳米金为晶种,用柠檬酸钠还原硝酸银制备了平均粒径为30 nm的（Au）核（Ag）壳纳米微粒,用高速离心纯化除去过量的柠檬酸三钠获得了较纯的（Au）核（Ag）壳纳米微粒,其吸收峰位于393nm处.在pH 4.4的HAc-NaAc缓冲溶液中,Fenton反应产生的羟基自由基可以氧化（Au）核（Ag）壳纳米微粒银层生成银离子,导致393 nm处的吸光度降低.H2O2的浓度（c）在6.58～421.1μmol/L范围内与393 nm处的吸光度降低值ΔA393 nm呈良好的线性关系,回归方程为ΔA393 nm=0.00111c＋0.0210,相关系数为0.9908,检出限为1.73μmol/L.本方法用于废水样品测定,结果满意.

Using 10 nm nanogold as seeds, the （An） fAg）shell nanoparticles were prepared in the presence of AgNO3 and trisodium citrate dehydrate, and they were purified by high-speed centrifugation to remove the excess trisodium citrate. The absorption peak of the purified （Au） fag） shell nanoparticles is at 393 nm. In pH = 4.4 HAc-NaAc buffer solution, hydroxyl radical produced from Fenton reaction oxidized the outer silver layer of the nanoparticles to form Ag ＋ , and resulted in decreasing of the absorbance value at 393 nm. The concentration of H2O2 in the range of 6.58-421. 1 μmol/L was linear to the decreased absorbance at 393 nm （△A393 nm）. Its regression equation was △A393 nm=0. 00111c ＋ 0. 0210, and the correlation coefficient was 0. 9908, with a detection limit of 1.73 μmol/L. This method was applied to the detection of H2O2 in wastewater, with satisfactory results.