A Note on Aspects of Sample Preparation for Drug Analysis in Serum by Capillary Electrophoresis

Abstract

Drug analysis in a complex matrix like serum or plasma is one of the most challenging tasks for an analytical chemist. Knowledge of the drug molecule and possible matrix compounds as well as the analytical measurement technique all need to be considered when searching for a successful analytical quantification method. For the analysis of polar, water-soluble drug molecules, the analytical technique of choice has traditionally been high performance liquid chromatography (HPLC). However, in many instances the lack of separation efficiency restricts the use of HPLC. In biomedical analysis the requirements for an analytical technique are high resolution and selectivity of the separation system, especially when general detection, e.g. UV absorbance, is used. The compatibility of the injected solution with the analytical system is essential. Furthermore the analytical method should remain stable and precise over long analysis periods when a large number of samples are analysed.