基于对氨基苯甲酰胺修饰的金纳米粒子比色测定水样中痕量杀草强

Colorimetric assay of trace amitrole in water with p-aminobenzamide-modified gold nanoparticles

采用柠檬酸钠还原法合成粒径13nm的金纳米粒子,并利用对氨基苯甲酰胺(AMIDE)对其进行表面修饰得到功能化的金纳米粒子(AMIDE-AuNPs)。实验发现,在一定的pH条件下,杀草强能诱导AMIDE-AuNPs聚集,金纳米粒子溶液由酒红色变为蓝色。因此以对氨基苯甲酰胺修饰的金纳米粒子为探针,建立了快速检测杀草强的比色方法。优化后的最佳实验条件为:杀草强与AMIDE-AuNPs反应平衡时间3min,缓冲液pH=4.0。在优化条件下,检测杀草强的线性范围为0.10~0.90mg·L^(-1),检测限(LOD)为0.02mg·L^(-1)。本方法具有简单、快速、灵敏、选择性好等优点,对实际水样中的杀草强进行检测,加标回收率为96.7%~108%,相对标准为1.9%~7.6%。

The 13 nm gold nanoparticles（AuNPs）were synthesized through the reduction of HAuCl_4 with sodium citrate,and the p-Aminobenzamide was assembled on the surface of AuNPs.With an appropriate pH value,AMIDE-AuNPs was induced to aggregate by the addition of amitrole,accompanied with the color change of AuNPs solution from wine red to blue.Thus,using PABA-AuNPs as colorimetric probe,a rapid assay for amitrole was proposed.The optimal experiment conditions were reaction equilibrium time=3 min,pH=4.0.Under the optimum conditions,the method showed a linear response range of 0.10-0.90 mg·L-（-1） for the amitrole with a detection limit being 0.02 mg·L（-1）.The proposed method has been successfully applied to the determination of amitrole in water samples with spiked recoveries of 96.7%-108% and relative standard deviation（RSD）of 1.9%-7.6%,respectively.