Pharmaceutical analysis micellar electrokinetic chromatography

Nishi, H. and Terabe, S., Application of micellar electrokinetic chromatography to pharmaceutical analysis, Electrophoresis, 11, 691, 1990. 

Dedicated applications of capillary zone electrophoresis (CZE) coupled to MS are discussed, particularly in the field of drug analysis. Development of other capillary-based electrodriven separation techniques such as non-aqueous capillary electrophoresis (NACE), micellar electrokinetic chromatography (MEKC), and capillary electrochromatography (CEC) hyphenated with MS are also treated. The successful coupling of these electromigration schemes with MS detection provides an efficient and sensitive analytical tool for the separation, quantitation, and identification of numerous pharmaceutical, biological, therapeutic, and environmental compounds. 

Micellar electrokinetic chromatography is applied for the analysis of a wide variety of organic substances, ionic and nonionic in nature. For instance, for the determination of the content of active pharmaceutical ingredients in tablets, creams, and injectables, the MEKC mode often offers advantages over the CZE mode. 

Several modes of CE have been described in the literature over past decade [6, 7], The most common are open tubular or capillary zone electrophoresis (CZE), micellar electrokinetic chromatography (MEKC), microemulsion elec-trokinetic chromatography (MEEKC), capillary electrochromatograpy (CEC), capillary gel electrophoresis, capillary isoelectric focusing and capillary iso-tachophoresis. Three recent reviews by Watzig [113], Tagliaro etal. [114] and Riekkola etal. [115] summarise the current method development options available to manipulate selectivity. In pharmaceutical analysis, CZE, MEKC, MEEKC and CEC are commonly used. 

Kim JB and Terabe S (2003) On-line sample preconcentration techniques in micellar electrokinetic chromatography. Journal of Pharmaceutical and Biomedical Analysis 30 1625-1643. 

H. Huang, Y. C. Lai, C. W. Chiu, J. M. Yeh, Comparing micellar electrokinetic chromatography and microemulsion electrokinetic chromatography for the analysis of preservatives in pharmaceutical and cosmetic products./. Chromatogr. A, 2003, 993, 153-164. 

After a short introduction into the relevance of Impurity profiling for regulatory authorities, public health, and the pharmaceutical industry, an overview is presented based on the various modes of capillary electrophoresis that have been used in drug impurity analysis. The applications of capillary zone electrophoresis, non-aqueous capillary electrophoresis, micellar electrokinetic capillary chromatography, microemulsion electrokinetic capillary chromatography, capillary gel electrophoresis, and capillary electrochromatography are presented consecutively. 

Altria, K. D., and Smith, N. W. (1991). Pharmaceutical analysis by capillary zone electrophoresis and micellar electrokinetic capillary chromatography. /. Chromatogr. 538, 506-509. 

Altria KD, McLean R. Development and optimisation of a generic micellar electrokinetic capillary chromatography method to support analysis of a wide range of pharmaceuticals and excipients. J Pharm Biomed Anal 1998 18 807-813. 

Capillary zone electrophoresis (CE) is a relatively new analytical method currently under investigation for use in research and control laboratories for the analysis of ionic forms of vitamins. Micellar electrokinetic capillary chromatography (MECC) is a modification of CE which allows the separation of both neutral and ionic forms using buffers with micellar additives. Both methods have been used to separate water-soluble vitamins but very rarely pantothenic acid, which has only been analyzed by this technique in model mixtures and pharmaceuticals. 

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