有序金纳米柱SERS基底制备及苏丹Ⅱ的拉曼光谱

Preparation of order gold nanopillar array and SERS spectra of SudanⅡ

苏丹Ⅰ~Ⅳ是色泽鲜艳的化学物质,被非法用于食品添加剂,损害人们身体健康。表面增强拉曼光谱(SERS)借助金属纳米结构的表面等离激元共振(SPR)效应,具有很高的检测灵敏度,可用于苏丹分子的快速检测。本文中,笔者制备了有序金纳米柱二维阵列结构,作为SERS基底,用于苏丹Ⅱ的SERS检测。为了更好地理解金纳米柱阵列结构对苏丹Ⅱ的SERS增强效应,结合有限元方法计算,分析了金纳米阵列结构与SPR效应的关系,并结合密度泛函理论(DFT)计算分析了SERS光谱与分子结构的关系。这有利于进一步提高SERS检测灵敏度。结果表明,对于苏丹Ⅱ的SERS检测,最低浓度为0.05 mmol/L,DFT计算确定苏丹Ⅱ的结构为trans NH异构体。

SudanⅠ-Ⅳis a brightly colored chemical,and illegally used in food to harm people′s health.With the help of SPR effect of metal nanostructures,surface enhanced Raman spectroscopy(SERS)has high detection sensitivity and can be used for rapid detection of Sudan dye.In this study,ordered gold nanopillar arrays were prepared and used as SERS substrates for SERS detection of SudanⅡ.In order to better understand the SERS enhancement effect of gold nanopillar array on SudanⅡ,the relationship between the structure of gold nanopillar array and SPR effect is analyzed by finite element method,and the relationship between SERS spectrum and molecular structure is analyzed by density functional theory.This result show that for SudanⅡ,the lowest concentration of SERS detection is 0.05 mmol/L and the structure is the trans-NH isomer.