农药残留严重影响人类身体健康与生命安全,故亟需建立一种简单高效的农药残留快速检测方法。本文以金纳米溶胶作为表面增强拉曼光谱(SERS)的增强基底,结合便携式拉曼光谱仪,实现了倍硫磷与对硫磷等常用有机磷农药的多靶标同时检测。结果表明倍硫磷和对硫磷分别在1053 cm-1,1216 cm-1和857 cm-1,1112 cm-1处具有特征拉曼谱峰,且两者互不干扰。同时进一步研究表明,倍硫磷和对硫磷的浓度与其特征拉曼谱峰强度线性相关,故可实现定量检测,其中倍硫磷检测限可达0.01 μg/mL对硫磷检测限可达0.025 μg/mL。同时,该SERS方法可直接用于菠菜实际样品中多种农药残留的多靶标快速检测,检测限达到0.05 μg/mL。该SERS方法具有方便、快速、灵敏度高、多靶标同时检测等优点,有望实现农药残留的现场快速检测。

Pesticide residue is a significant problem in agriculture that greatly affects human health and life safety.Therefore,it is an urgent need to develop simple and effective method for the rapid detection of trace pesticide residue.In this work,combined with a portable Raman spectrometer,a surface-enhanced Raman spectroscopy (SERS)method was developed to achieve the rapid detection of trace organophosphorus pesticides including fenthion and parathion using gold sols as the SERS substrate.It was found that the characteristic Raman peaks of fenthion and parathion located at 1053 cm-1,1216 cm-1 and 857 cm-1,1112 cm-1,respectively,thus enabling the multi-target analysis simultaneously.The concentrations of fenthion and parathion display a linear relationship with their corresponding Raman intensities with a detection limit of fenthion can reach 0.01 μg/mL and parathion can reach 0.025 μg/mL.Furthermore,the SERS method developed here was successfully applied in the direct detection of fenthion and parathion residue on practical spinach samples with a detection limit of 0.05 μg/mL.This work demonstrates that SERS can be a convenient,rapid,sensitive and multi-target analysis method for the on-site detection of pesticide residues.