Au@Ag纳米粒子在农药SERS光谱分析中的应用

Application of SERS spectroscopic technique in pesticide analysis by using Au@Ag core-shell nanoparticles as substrates

随着现代农业的发展,多种农药被广泛应用于农田,果园和温室等场所。由于大多数农药对生态环境、动物和人类健康都有害,因此建立快速、灵敏和实时检测环境与食品中农药含量的技术显得越来越重要。本文论述了用作表面增强拉曼散射(SERS)光谱基底的金核银壳纳米粒子(Au@AgNPs)的制备方法,以及将其用于苹果表面农药百草枯Paraquat(PQ)残留量的检测分析,检测限为4.69×10^(-9) M。研究工作表明,相对于单纯的金溶胶(AuNPs)或者银溶胶(AgNPs),Au@AgNPs在该农药的SERS光谱分析中表现出更好的SERS增强效应和检测效果。Au@AgNPs在浓度为1.3×10^(-7)M的低浓度条件下仍可检测到PQ。因此,具备核壳结构的Au@Ag溶胶可用于实时和灵敏检测果皮表面的农药残留,这为相关检测技术的建立提供了有益的信息。

With the development of modern agriculture,multiple pesticides have been used widely in farmlands,orchards,greenhouses and so on.Because the most of pesticides are harmful to environment,animals and human health,finding sensitive and rapid detection techniques for pesticides is more and more essential today.Here,Au@Ag nanoparticles are used as a surface enhanced Raman scattering substrate to detect the residual of Paraquat(PQ)pesticide on apple surface,and the detection limit is 4.69×10^(-9) M.In this study,Au@Ag colloidal sol exhibits much better surface enhanced Raman scattering effect than that of gold or silver colloidal sol.By using Au@Ag colloidal sol as a substrate,PQ can be detected by SERS spectroscopic technique even in such a low concentration of 1.3×10_(-7)M.As a result,the Au@Ag core-shell nanoparticles can be used as a valuable SERS substrate to detect pesticide residual on fresh apple skins in real time and on site.