纳米金比色法快速检测蔬菜中毒死蜱方法的研究

摘要

A gold nanoparticles-based colorimetric assay for rapid detection of chlorpyrifos in vegetable was developed. Based on the coordination effect of the oxygen-containing groups and lanthanum (III) functionalized gold nanoparticles, chlorpyrifos could induce the aggregation of lanthanum functionalized gold nanoparticles, thereby resulting in red-to-blue color change. So the concentration of chlorpyrifos could be determined by monitoring with the naked eye or a UV-vis spectrometer. The absorption difference of the assay exhibited a linear correlation to chlorpyrifos concentration in the range from 5 ×10-10 mol/L to 5 ×10-7 mol/L with a limit of detection of 0.1 nmol/L (S/N=3). The merits (such as simplicity, low cost and visual colorimetry) make the proposed method for on-site screening of chlorpyrifos in vegetable.%建立了一种快速检测蔬菜中毒死蜱残留量的比色方法。该方法基于镧（III）功能化纳米金与含氧酸根的配位，加入毒死蜱引起功能化的金纳米粒子发生聚集，使溶液出现红色到蓝色的变化，可以通过用肉眼观察颜色或者用紫外分光光度法检测其吸光度的变化来检测毒死蜱的含量。毒死蜱浓度在5×10-10 mol/L~5×10-7 mol/L范围内，呈良好的线性关系，检出限为0.1 nmol/L（S/N=3）。该方法操作简单、成本低、比色明显，可用于蔬菜中毒死蜱残留的现场检测。