Chiu Chen-Wen, Liang Hsin-Hui, Huang Hsi-Ya
R&D Center for Membrane Technology, CYCU, Department of Chemistry and Center for Nanotechnology at CYCU, Chung Yuan Christian University, Chung-Li, Taiwan, ROC.
Electrophoresis. 2007 Nov;28(22):4220-6. doi: 10.1002/elps.200700371.
A simple method for the separation and characterization of five nicotine-related alkaloids by NACE employing UV and MS detections is described here for the first time. Several factors, including NACE parameters (compositions of running solution) and MS parameters (such as nature and flow rate of sheath liquid, pressure of nebulization gas, and flow rate of dry gas), were optimized in order to obtain both an adequate CE separation and high MS signals for the alkaloid compounds used in this study. A reliable CE separation of five alkaloids was achieved in 50 mM ammonium formate that was dissolved in an ACN/methanol mixture (50:50, v/v) of pH* 4.0 (apparent pH 4.0). The optimal electrospray MS measurement was carried out in the positive ionization mode using a coaxial sheath liquid composed of isopropyl alcohol and water in the ratio of 80:20 v/v at a flow rate of 180 microL/h. In addition, the proposed NACE method was also applied in the analyses of alkaloids in several products including chewing gums, beverages, and tobaccos. This NACE-MS method was found to provide a better detection ability and separation resolution for the analysis of nicotine alkaloids when compared to other aqueous CE-MS reports.
本文首次描述了一种采用紫外和质谱检测的非水毛细管电泳(NACE)法分离和鉴定五种与尼古丁相关生物碱的简单方法。为了实现本研究中生物碱化合物的充分毛细管电泳分离和高质谱信号,对包括NACE参数(运行溶液组成)和质谱参数(如鞘液的性质和流速、雾化气体压力和干燥气体流速)在内的几个因素进行了优化。在溶解于pH值为4.0(表观pH值4.0)的乙腈/甲醇混合物(50:50,v/v)中的50 mM甲酸铵中,实现了五种生物碱的可靠毛细管电泳分离。使用由异丙醇和水按80:20 v/v比例组成的同轴鞘液,流速为180 μL/h,在正离子模式下进行最佳电喷雾质谱测量。此外,所提出的NACE方法还应用于几种产品(包括口香糖、饮料和烟草)中生物碱的分析。与其他水性毛细管电泳-质谱报告相比,该NACE-质谱方法在尼古丁生物碱分析中具有更好的检测能力和分离分辨率。