Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA.
J Chromatogr A. 2011 Sep 23;1218(38):6750-5. doi: 10.1016/j.chroma.2011.07.044. Epub 2011 Jul 23.
Electrokinetic supercharging (EKS) combines field-amplified sample injection with transient isotachophoresis (tITP) to create a powerful on-line preconcentration technique for capillary electrophoresis. In this work, EKS is enhanced with a positive pressure (pressure-assisted EKS, or PA-EKS) during injection to improve stacking of non-steroidal anti-inflammatory drugs (NSAIDs). Several parameters, including buffer composition and concentration, terminating electrolyte, organic modifier, and injection voltage and injection time of both terminating electrolyte and sample were optimized. Detection limits for seven NSAIDs were determined and an enhancement in sensitivity of almost 50,000-fold was obtained. The PA-EKS method has the potential to be a simple MS compatible preconcentration method to improve the sensitivity of CE.
电动强化（EKS）将场放大样品进样与瞬时等速电泳（tITP）相结合，为毛细管电泳创建了一种强大的在线浓缩技术。在这项工作中，在进样过程中通过正压（压力辅助电动强化，或 PA-EKS）来增强 EKS，以改善非甾体抗炎药（NSAIDs）的堆积。优化了包括缓冲液组成和浓度、终止电解质、有机溶剂、以及终止电解质和样品的进样电压和进样时间在内的多个参数。测定了七种 NSAIDs 的检测限，灵敏度提高了近 50,000 倍。PA-EKS 方法有可能成为一种简单的 MS 兼容的浓缩方法，以提高 CE 的灵敏度。
