金铂纳米粒子比色法对茶水中汞离子的检测

文章在金纳米粒子(gold nanoparticles, AuNPs)基础上制备具有核壳结构的金铂(Au@Pt)纳米粒子，并对合成的Au@Pt纳米粒子进行表征；茶水中的 $ Hg^{2+} $可使Au@Pt纳米粒子过氧化物酶活性降低，从而引起 $ 3,3',5,5' $-四甲基联苯胺(TMB)- $ H_{2}O_{2} $底物溶液颜色变化，基于此，文章提出一种快速检测茶水中 $ Hg^{2+} $的比色法。当待测物中 $ Hg^{2+} $浓度在1~50nmol/L范围时，此反应体系的紫外分光吸光度与 $ Hg^{2+} $浓度有良好的线性关系，该方法的检测灵敏度为0.52nmol/L。与其他传统的 $ Hg^{2+} $检测方法相比，文章所提比色法无需样品前处理，具有操作简单、检测快速、灵敏度高和特异性好等优点，可用于茶水中痕量 $ Hg^{2+} $的定量检测与早期预警。

In this paper, Au@Pt nanoparticles with core-shell structure were prepared on the basis of gold nanoparticles(AuNPs). The synthesized Au@Pt nanoparticles were characterized. The $ Hg^{2+} $ in tea can reduce the peroxidase activity of Au@Pt nanoparticles, resulting in a change in the color of the $ 3,3',5,5' $-tetramethylbenzidine(TMB)- $ H_{2}O_{2} $ substrate solution. On this basis, a colorimetric method for rapidly detecting $ Hg^{2+} $ in tea was developed. The experimental results show that when the $ Hg^{2+} $ concentration in the analyte is in the range of 1-50 nmol/L, there is a good linear correlation between the UV absorbance and the concentration of $ Hg^{2+} $, and the detection sensitivity of the method is 0.52 nmol/L. Compared with other traditional $ Hg^{2+} $ detection methods, the colorimetric method proposed in this paper does not require sample pretreatment, and has the advantages such as simple operation, rapid detection, high sensitivity and good specificity. It is expected to be applied in the quantitative detection and early warning of trace $ Hg^{2+} $ in tea.