Conductivity detection in capillary zone electrophoresis: Inspection by PeakMaster
Conductivity detection in capillary zone electrophoresis: Inspection by PeakMaster
复制标题
毛细管区带电泳中的电导率检测：通过 PeakMaster 进行检查
作者：
M. Jaros;T. Soga;T. van de Goor;B. Gaš
毛细管区带电泳中电导检测的信号与分析物迁移率和背景电解质(BGE)共离子的迁移率之差成正比的一条简单规则仅适用于具有完全电离的电解质的系统。在弱电解质的区带电泳体系中，分析物峰的电导信号和电迁移色散都取决于电导和pH效应。这允许优化BGE的组成，以提供良好的分析物电导信号，同时仍保持电迁移色散接近于零，而不考虑样品的进样量。可以同时实现电导检测中最小的电迁移色散和高灵敏度的要求。PeakMaster软件用于在高碱性pH条件下检测通常用于糖(碳水化合物、糖)分离的BGE。结果表明，直接电导检测和间接电导检测这两个术语具有误导性，不应使用。
A simple rule stating that the signal in conductivity detection in capillary zone electrophoresis is proportional to the difference between the analyte mobility and mobility of the background electrolyte (BGE) co‐ion is valid only for systems with fully ionized electrolytes. In zone electrophoresis systems with weak electrolytes both conductivity signal and electromigration dispersion of analyte peaks depend on the conductivity and pH effects. This allows optimization of the composition of BGEs to give a good conductivity signal of analytes while still keeping electromigration dispersion near zero, regardless of the injected amount of sample. The demands to achieve minimum electromigration dispersion and high sensitivity in conductivity detection can be accomplished at the same time. PeakMaster software is used for inspection of BGEs commonly used for separation of sugars (carbohydrates, saccharides) at highly alkaline pH. It is shown that the terms direct and indirect conductivity detection are misleading and should not be used.