基于硫代巴比妥酸修饰的银纳米粒子对Pb^(2+)的比色分析研究

Colorimetric detection of Pb^(2+) based on thiobarbituric acid (TBA)-functionalized Ag nanoparticles

将硫代巴比妥酸(thiobarbituric acid,TBA)修饰在新制备的银纳米粒子(Ag nanoparti-cles,AgNPs)表面,制备成小型的TBA-AgNPs比色传感器.在相同条件下利用TBA-AgNPs的颜色变化对16种不同金属离子进行分析测定,发现当pH值为11时,该传感器只对Pb2+有明显响应,其他离子无明显干扰,且A540/A402与Pb2+的浓度在3.97～27.8μmol/L范围内呈良好的线性关系.该方法具有简便快速,选择性好,结果可视化等优点,有望用于环境样品中Pb2+的快速测定.

A simple and highly selective thiobarbituric acid-modified silver nanoparticles（AgNPs） was synthesized and used as a probe for the colorimetric detection of lead ions（Pb2＋）,based on the fact that Pb2＋ ions induced the aggregation of the AgNPs as a consequence of a chelation process between Pb2＋ ion and thiobarbituric acid on the AgNPs.It was found that,at pH 11,TBA-AgNPs displayed good selectivity to Pb2＋ ions,and other 15 kinds of metal ions did not interfere.The A540/A402（ratio of adsorption value at 540 and 402 nm） showed a good linear relationship with Pb2＋ concentration（c） ranging from 3.97 μmol/L to 27.8 μmol/L.The present method was simple,rapid,highly selective and visible,which offered good potential for rapid detection of Pb2＋ in environmental samples.