自组装有序纳米银线表面增强拉曼光谱检测牛奶中三聚氰胺

Determination of Melamine in Milk by Surface Enhanced Raman Scattering Technique Based on Self-Assembly Ordered Silver Nanowires

制备具有表面增强拉曼散射(SERS)增强效果的基底是获得灵敏SERS检测的基础。本研究以多元醇法合成、流体流动法组装制备的有序纳米银线作为三聚氰胺的SERS增强基底,实现了样品中痕量三聚氰胺的快速灵敏检测。通过理论计算及实验考察得到了三聚氰胺的拉曼特征峰,优化了三聚氰胺在有序纳米银线基底上的SERS检测条件。在p H=8、水为溶剂、溶剂挥发时间为14 min的最佳条件下,三聚氰胺特征峰强度与浓度在0.05~1.00 mg/L范围内呈现良好的线性关系,其线性相关系数R=0.997,检测限为0.05 mg/L。在牛奶中添加不同浓度的三聚氰胺,其回收率为89.7%~109.2%,相对标准偏差低于6.8%。本方法对三聚氰胺检测具有很好的灵敏度和稳定性,为其它小分子化合物的SERS检测提供技术支持。

The fundamental technique of surface enhanced Raman scattering（SERS） is to fabricate a sensitive SERS substrate.A rapid and sensitive detection of trace amounts of melamine in sample was developed,in which a SERS substrate based on ordered silver nanowires（Ag NWs） was synthesized and assembled via polyol-fluid flow method.The characteristic Raman peak of melamine was obtained through the theoretical calculation and experimental investigation.And the detection conditions of melamine SERS on the ordered silver nanowire substrate were optimized.Under the optimum conditions including p H = 8,water as solvent and 14 min of solvent evaporation time,a good linearity（R = 0.997） between characteristic peak intensity and melamine concentration was obtained in the range of 0.05-1.00 mg/L with the detection limit of0.05 mg/L.The recovery of melamine spiked in milk sample was from 89.7% to 109.2% and the relative standard deviation was below 6.8%.The method exhibited good sensitivity and stability for the detection of melamine,and could provide the technical support for the SERS detection of other small molecule compounds.