Capillary Electrophoresis – A High Performance Analytical Separation Technique

Abstract

Capillary electrophoresis (CE) is often one of the preferred techniques in pharmaceutical quality control and in clinical chemistry, particularly considering the high selectivity and lower costs compared to HPLC. The precision of CE is as good as in liquid chromatography (LC). The sample-throughput is high due to short analysis times. Efforts for sample pre-treatment are usually minor in CE. Urine and even blood plasma can be directly injected without further pre-treatment. After summarising the basic principles of CE, general strategies for method development are described to achieve selective, efficient, precise, fast, sensitive, and validated methods. Sample pre-treatment requirements are discussed. Standard buffer recipes, surfactants used in micellar electrokinetic chromatography (MEKC), chiral selectors, useful buffer additives, actions to deal with complex matrices, and aspects of validation have been collected. Other techniques that can be performed with CE instruments, such as capillary isoelectric focusing (CIEF), capillary isotachophoresis (CITP), and capillary electrochromatography (CEC), are briefly discussed.