Micellar electrokinetic chromatography surfactant

See also-. Chromatography Overview. Liquid Chromatography Overview Principies Reversed Phase Ion Pair. Micellar Electrokinetic Chromatography. Surfactants and Detergents. 

R., Khaledi, M. G. Quantitative structure-activity relationships studies with micellar electrokinetic chromatography. Influence of surfactant type and mixed micelles on estimation of hydrophobicity and bioavailability. J. Chromatogr. A 1996, 727, 323-335. 

Ozaki, H. and Terabe, S., On-line micellar electrokinetic chromatography-mass spectrometry with a high molecular-mass surfactant, ]. Chromatogr. A, 794, 317, 1998. 

Micellar electrokinetic chromatography is based on the effects of the interaction of the analyte with surfactant micelles on the electrophoretic process. 

C.-E. Lin, Y.-T. Chen and T.-Z. Wang, Separation of benzenediamines, benzenediols and aminophenols in oxidative hair dyes by micellar electrokinetic chromatography using cationic surfactants. J. Chromatogr.A, 837 (1999) 241-252. 

Naess, O., and Rasmussen, K. E. (1997). Micellar electrokinetic chromatography of charged and neutral drugs in acidic running buffers containing a zwitterionic surfactant, sulfonic acids or sodium dodecyl sulphate — separation of heroin, basic by-products and adulterants. /. Chromatogr. A 760, 245-251. 

Shamsi, S. A. (2001). Micellar electrokinetic chromatography-mass spectrometry using a polymerized chiral surfactant. Anal. Chem. 73, 5103-5108. 

Micellar electrokinetic chromatography is a hybrid of electrophoresis and chromatography. Introduced by Terabe in 1984 (9), MEKC is one of the most widely used CE modes. Ionic micelles, formed from surfactants added... 

Figure 26-33 Separation of enantiomers of eight p blocker drugs by micellar electrokinetic chromatography at pH 8.0 in a 120-cm capillary at 30 kV. Micelles were formed by a polymer surfactant containing L-leucinate substituents for chiral recognition. The structure of one compound is shown. [From C. Akbay. S, A. A. Rizvi. and S. A. Shamsi, "Simultaneous Enantiosepcration and Tandem UV-MS Detection of Eight p-Blockers in Micellar Electrokinetic Chromatography Using a Chiral Molecular Micelle Anal. Chem. 2005, 77.1672.]...

Micellar electrokinetic chromatography (MEKC) is a modality of liquid chromatography having a surfactant molecule in the form of a micelle, which was introduced by Terabe et al. in 1984 [38]. The formation and separation occur in the capillary and, hence, it is also called micellar electrokinetic capillary chromatography (MECC). This modality is useful for some specific molecules having solubilities in micelles and, therefore, utilized for the separation and identification of such compounds with great efficiency, reproducibility, and low levels of detections. The most commonly used compounds for micelle formation are sodium dodecyl sulfate (SDS), sodium tetradecyl sulfate, sodium decanesulfonate, sodium /V-lauryl-/V-mcthyllauratc, sodium... 

Sainthorant C, Morin P, Dreux M, Baudry A, Goetz N. Separation of phenylenedia-mine, phenol and aminophenol derivatives by micellar electrokinetic chromatography. comparison of the role of anionic and cationic surfactants. J Chromatogr A 1995 717 167. 

Mwongela, S.M., Numan, A., Gill, N.L., Agbaria, R.A., and Warner, I.M. 2003. Separation of achiral and chiral analytes using polymeric surfactants with ionic liquids as modifiers in micellar electrokinetic chromatography. Analytical Chemistry, 75 6089-96. 

Conceptually. CE enantioseparations are mainly applied to charged SAs. Micellar electrokinetic chromatography (MEKC) (introduced by Terabe et al. in 1984 488 ), in contrast, permits the separation of electrically neutral compounds. In enantiomer separation by MEKC. ionic pseudo-stationary phases, such as chiral micelles composed of chiral SO moieties, which migrate according to their electrophoretic mobility, may interact stereoselectively with the solutes to be separated. MEKC with synthetic (e.g. A-dodecoxycarbonylvalines, commercialized as SDVal by Waters) 1489.490) or naturally occurring chiral surfactants (e.g. bile salts) 1491-494). and cyclodextrin-moditied MEKC (most often SDS/CD combinations) 1495-498) are the mo.st widely used selector systems in MEKC. The topic of MEKC enantioseparation has been reviewed by Nishi )499). 

Otsuka, K. and S. Terabe, Micellar electrokinetic chromatography, Bull. Chem. Soc. Jpn. 71 2465 (1998). Otsuka, K. and S. Terabe, Enantiomer separation of drugs by micellar electrokinetic chromatography using chiral surfactants, /. Chromatogr. A 875 163 (2000). 

Yang, S.Y., Bumgarner, J.G., Kruk, L.F. and Khaledi, M.G. (1996). Quantitative Structure-Activity Relationships Studies with Micellar Electrokinetic Chromatography Influence of Surfactant Type and Mixed Micelles on Estimation of Hydrophobicity and Bioavailability. J.Chro-mat, 721A, 323-335. 

The technique is therefore particularly suited to water-soluble species which possess a charge, which includes most dyes. Variations from the main technique (often referred to as capillary zone electrophoresis, CZE) do exist and these include the use of surfactants in the buffer to create micelles (often thought of as creating a pseudo-stationary phase inside the capillary) which then improve the separation of neutral species (and frequently charged molecules) owing to hydrophobic interactions. The term micellar electrokinetic chromatography (MECC or MEKC) is often used for CE separations carried out with the aid of a micellar buffer solution. 

Another modification of CE is micellar electrokinetic chromatography (MEKC), which is widely used for the separation of nonpolar compounds. The molecules in question partition into micelles (nonpolar layer) with mechanisms similar to those observed with reverse-phase chromatography. An anionic surfactant, sodium dodecyl sulfate, is commonly used as a micellar... 

K Otsuka, S Terabe. Enantiomer separation of drugs by micellar electrokinetic chromatography using chiral surfactants. J Chromatogr A 875 163-178, 2000. 

H Nishi, T Fukuyama, M Matsuo, S Terabe. Effect of surfactant structures on the separation of cold medicine ingredients by micellar electrokinetic chromatography. J Pharm Sci 79 519-523 1990. 

Capillary electrophoresis (CE) has emerged as an efficient and rapid separation technique in recent years. Its high efficiency has been employed in many applications such as in the analysis of environmental pollutants.Different approaches have been adopted to enhance selectivity for the analysis of different types of compounds. There are two approaches most commonly used to improve CE separations the addition of modifiers into the electrophoretic medium and the modification of the column. Examples of the first approach include the addition of surfactants into the electrophoretic medium as in micellar electrokinetic chromatography (MEKC), and the use of organic solvents,cyclodextrines, " " or bile salts " as buffer modifiers. Examples of the second method include the use of gel-filled columns (capillary gel electrophoresis) " and the coating of the capillary wall surface. " " ... 

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