通过化学法合成了具有表面增强拉曼散射(SERS)活性的银胶体,利用透射电子显微镜和紫外可见光谱仪分别对银胶体的形貌和光学性质进行了表征;采用这种衬底对水相中微量的芬太尼进行了SERS检测研究,并对芬太尼的SERS信号进行了归属,考察了各种实验条件对SERS检测的影响。实验结果表明,增大银胶体浓度有利于芬太尼SERS信号的检测;随着团聚剂氯化钠浓度增大芬太尼的SERS信号强度会先增大后减小,即团聚剂浓度存在一个最佳值;在优化的实验条件下芬太尼的检测限可以达到0.1ppm量级。

Surface-enhanced Raman scattering(SERS)-active silver colloid was prepared conveniently by a chemical method and characterized by transmission electron microscopy (TEM)and UV-vis spectroscopy.Then,the silver colloid was used as SERS substrate to detect trace fentanyl in aquous solution and the SERS peaks were assigned.The influence of concentrations of silver colloid and aggregating agent(NaCl)to the SERS spectrum was also investigated.The results indicated that the higher the concentration of silver colloid was,the stronger SERS intensity of fentanyl was detected.Along increasing concentration of NaCl,fentanyl SERS intensity firstly increased and then decreased,that was,there was an optimized concentration of NaCl.The limit of detection for fentanyl was around 0.1 ppm under the optimized condition.