Electrokinetic chromatography: an historical review of developments in theory and practice

Varejão, Jorge M. T. B.; Costa, M. Conceição Cruz

Palavras-chave: Electrokinetic Chromatography, Pseudostationary phase, Mass Spectrometric Detection, Analyte Focusing, Selectivity, Band Broadening.

Resumo: During three decades since the introduction of electrokinetic chromatography (EKC), a large number of research and development efforts have defined the technique and demonstrated numerous applications. Theory has been developed and the fundamental factors affecting performance have been characterized, allowing rational method development and optimization. Numerous materials have been introduced for use as pseudostatonary phases, and their separation performance and selectivity characterized. EKC has been applied to numerous analytical problems, and also to characterize both analytes and pseudostationary phase materials. Although it was originally thought to be an insurmountable challenge, EKC has been combined with mass spectrometry to provide selective, qualitative and sensitive detection. EKC has also been demonstrated to be effective for online analyte focusing using various approaches, thus helping to overcome the low concentration sensitivity of the technique. This review provides introduction to EKC for the novice, and highlights important fundamental, theoretical and practical developments in the field.

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