中文摘要：

介绍了一种基于表面增强拉曼光谱技术（SERS）的简单快速检测低浓度铬酸根离子的方法.通过介质中水与铬酸根离子以及修饰在金基底和金纳米粒子表面的羧酸根形成氢键而构建＂巯基苯甲酸-金基底/铬酸根-水/巯基苯甲酸-金纳米粒子＂三明治结构.通过检测标记分子的SERS信号判断溶液中是否存在铬酸根离子.研究表明标记分子的SERS强度与铬酸根离子的浓度有关,随浓度增加SERS强度呈非线性增强,在10-9mol/L出现转折点.利用以上三明治结构,通过引入功能化的Fe2O3@Au核壳磁性纳米粒子,利用外加磁场可富集分离溶液中的铬酸根离子,经SERS检测表明10-5mol/L的铬酸根离子磁分离后其浓度降低了约4～6个数量级.

英文摘要：

A simple technique for the detection of low concentrations of chromium（VI） was developed based on the surface enhanced Raman spectroscopy （SERS）.By the hydrogen-bond of water between chro-mium（VI） and the carboxyl groups from mercaptobenzoic acid （MBA） attached to the Au plate surface and Au nanoparticles,the sandwich structure of ＂MBA modified Au plate substrate/chromium（VI）-water/MBA modified Au nanoparticles＂ was built for SERS detection.The existence of chromium（VI） ions was moni-tored by detecting the SERS signals of the reporter molecules.The results reveal that the SERS intensities of the reporter were relevant to the concentration of chromium（VI） ions.The SERS intensities changed non-linearly with the increase of the concentration and a significant increase in the SERS signal was ob-served on the concentration of 10-9 mol/L.Based on the above sandwich structure,functionalized Fe2O3@Au core-shell magnetic nanoparticles was introduced to enrich and separate chromium（VI） ions by the assistance of an external magnetic field.SERS detection showed that the concentration of chromium（VI） ions reduced by about 4～6 orders after the magnetic separation for the initial solution of 10-5 mol/L.