检测痕量纳米金的纳米催化光度法

在EDTA—NaOH介质中，金纳米微粒对盐酸联氨还原硫酸铜生成铜微粒这一慢反应具有较强的催化作用．铜微粒在750nm处产生一个吸收峰．随着纳米金浓度的增大，750nm处的吸光强度线性增大．对于粒径为10、30、50nm的纳米金，其线性范围、回归方程、检出限分别为0．12～1．68、0．36～2．80、1．00～5．00nmol／L，△A750nm=0．3205CAu＋0．0076、△A750nm=0．2201CAu＋0．0056、△A750nm=0．1150CAu＋0．0066，0．05、0．20、0．50nmol／L Au．分别对0．50、1．00nmol／L纳米金（d=10nm）平行测定10次，求得其相对标准偏差分别为4．2％、3．5％．

A New Nanocatalytic Spectrophotometric Method for Detection of Trace Nanogold

Gold nanoparticles in size of 10 nm, 30 nm and 50 nm were prepared by improved trisodium citrate reduction procedure. In media of EDTA-NaOH, nanogold exhibited strong catalytic effect on the slow particle reaction of Cu（Ⅱ） and N2H4HCl.The product of copper particles exhibited an absorption peak at 750 nm. When the concentration of nanogold increased, the absorption value at 750 nm enhanced linearly. For nanogold in size of 10,30 and 50 nm, their linear range, regress equation, detection limit are 0.12～1.68, 0.36～2.80, 1.00～5.00 nmol/L;△A750nm=0. 3205 CAu＋0. 0076, △A750m=0. 2201 CAu＋ 0. 0056, △A750nm=0. 1150 CAu＋ 0.0066;0.05, 0.20, 0.50 nmol/L Au, respectively. The 0. 50 and 1.00 nmol/L nanogold in size of 10 nm were determined by 10 times, their relative standard deviation was 4.2% and 3.5% respectively.