Water-soluble vitamins capillary electrophoresis

Capillary zone electrophoresis is a powerful tool for the separation of water-soluble vitamins, such as nicotinic acid and vitamin C, with high-pH borate or phosphate buffers. Most simultaneous separations have been performed for fat-soluble vitamins, such as vitamins A and E, by MEKC. Here, organic... 

L Fotsing, M Fillet, I Bechet, P Hubert, J Crommen. Determination of six water-soluble vitamins in a pharmaceutical formulation by capillary electrophoresis. J Pharm Biomed Anal 15 1113-1123, 1997. 

L Fotsing, B Boulanger, P Chiap, M Fillet, P Hubert, J Crommen. Multivariate optimization approach for the separation of water-soluble vitamins and related compounds by capillary electrophoresis. Biomed Chromatogr 14 10-11, 2000. 

Su, S.C., Chou, S.S., Hwang, D.F., Chang, P.C., and Liu, C.H., 2001. Capillary zone electrophoresis and micellar electrokinetic capillary chromatography for determining water-soluble vitamins in commercial capsules and tablets. Journal of Food Science. 66 10-14. 

Dinelli, G., and Bonetti, A., 1994. Micellar electrokinetic capillary chromatography analysis of water-soluble vitamins and multi-vitamin integrators. Electrophoresis. 15 1147-1150. 

Crevillen, A.G., Pumera, M., Gonzalez, M.C., and Escarpa, A. (2008) Carbon nanotubes disposable detectors in microchip capillary electrophoresis for water-soluble vitamins determination analytical possibilities in pharmaceutical quality control. 

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. 

A mixture of several water-soluble vitamins including calcium pantothenate was recently evaluated by CE by Jegle (83). The sample was analyzed in a 0.02 M sodium phosphate buffer (pH 7) and separated using a three-dimensional capillary zone electrophoresis system (flised-siUca, 50 pm i.d., straight, length to detector 400 mm, total length 485 mm, injection pressure 4.6 sec at 4 kPa, postinjection pressure 4 sec at 40 kPa, polarity positive, voltage 20 kV, capillary temperature... 

U Jegle. Separation of water-soluble vitamins via high-performance capillary electrophoresis. J Chromatogr A 652 495-501, 1993. 

A review on methods for analysis of urinary glycosaminoglycans has covered electrophoresis of enzymically produced di- and oligosaccharides. Micellar electrokinetic capillary chromatography, which is equivalent to capillary zone electrophoresis with a surfactant added to the carrier electrolyte, has been used with u.v. detection for the simultaneous determination of seven water-soluble vitamins including vitamin C and riboflavin phosphate. ... 

Nonaqueous capillary electrophoresis is a new technique that matured over the last couple of years to complement the electrophoretic techniques performed under aqueous conditions. Consequently, it extends the applicability of CE to those analytes that are insoluble or only sparsely soluble in water, including several classes of pharmaceutical compounds and long-chain fatty acids, vitamins, and surfactants, to name only a few. 

A recently proposed method (314) for the separation of fat-soluble vitamins by electrokinetic chromatography was further developed (315). The separation medium consisted of acetonitrile water (80 20 v/v) and contained tetradecylam-monium bromide as a pseudostationary phase. The high acetonitrile content was necessary to keep the hydrophobic vitamins in solution during electrophoresis. With the cathode placed at the capillary outlet, the fat-soluble vitamins were separated based on different hydrophobic interactions with the pseudo-stationary phase. The vitamins migrated in order of decreasing hydrophobicity prior to the electroosmotic flow. 

The work covers both the fat-soluble (Chapters 1—4) and the water-soluble (Chapters 5-13) vitamins, with emphasis on state-of-the-art chromatography, sample preparation, and final measurement. Following present analytical evolution, sections on recent techniques such as capillary electrophoresis and mass spectrometry have been added or expanded. Information on metabolism and biochemical function has also been revised to incorporate current knowledge. 

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