Micellar liquid chromatography

ESTIMATION OF RETENTION MODELS ADEQUACY IN MICELLAR LIQUID CHROMATOGRAPHY... 

The development of micellar liquid chromatography and accumulation of numerous experimental data have given rise to the theory of chromatographic retention and optimization methods of mobile phase composition. This task has had some problems because the presence of micelles in mobile phase and its modification by organic solvent provides a great variety of solutes interactions. 

Mass-action model of surfactant micelle formation was used for development of the conceptual retention model in micellar liquid chromatography. The retention model is based upon the analysis of changing of the sorbat microenvironment in going from mobile phase (micellar surfactant solution, containing organic solvent-modifier) to stationary phase (the surfactant covered surface of the alkyl bonded silica gel) according to equation ... 

The model was tested by the micellar liquid chromatography separ ation of the five rarbornicin derivatives and four ethers of hydroxybenzoic acid. Micellar mobile phases were made with the sodium dodecylsulfate and 1-pentanol or isopentanol as modifier. In all cases the negative signs of the coefficients x and y indicate that at transition of the sorbat from the mobile on the stationar y phase the number of surfactant monomers as well as the number of modifier molecules increases in its microenvironment. 

Micellar Liquid Chromatography, Alain Berthod and Celia Garcfa-Alvarez-Coque... 

Detroyer, A., VanderHeyden, Y., Cardo-Broch, S., Garda-Alvarez-Coque, M. C., Massart, D. L Quantitative structure-retention and retention-activity relationships of 3-blocking agents by micellar liquid chromatography. 

Berthod, A., Causes and remediation of reduced efficiency in micellar liquid chromatography, /. Chromatogr. A, 780, 191, 1997. 

Khaledi, M.G. and Breyer, E.D. Quantitation of hydrophobicity with micellar liquid chromatography. Anal. Chem., 61(9) 1040-1047, 1989. 

S. Carda-Broch, J. Esteve-Romero and M.C. Garca-Alvarez-Coque, Furosemide assay in pharmaceuticals by micellar liquid chromatography study of the stability of the drug, J. Pharm. Biomed. Anal., 23(5), 803-817 (2000). 

S Y Yang, MG Khaledi. Linear solvation energy relationships in micellar liquid chromatography and micellar electrokinetic capillary chromatography. J Chromatogr 692 301-310, 1995. 

M Molero-Monfort, Y Martfn-Biosca, S Sagrado, RM Villanueva-Camanas, MJ Medina-Hernandez. Micellar liquid chromatography for prediction of drug transport. J Chromatogr A 870 1-11, 2000. 

A. Berthod and C. Garcia-Alvarez-Coque, Micellar Liquid Chromatography (New York Marcel Dekker, 2000) S. Terabe, Micellar Electrokinetic Chromatography, Anal. Chem. 2004, 76, 240A U. Pyell, Micellar Electrokinetic Chromatography—From Theoretical Concepts to Real Samples (Review), Fresenius J. Anal. Chem. 2001, 371, 691. 

The various applications of micellar liquid chromatography are listed alphabetically in Table 1 according to sample type. The chromatographic parameters, instruments used for detection and elements analyzed are summarised. 

Fig. 5. Chromatogram of mixture of four arsenic standards using micellar liquid chromatography. Reprinted from Ding et al. [68] by permission of Elsevier Science.

S. Carda-Broch, I. Rapado-Martinez, J. Esteve-Romero and M. C. Garcia-Alvarez-Coque, Analysis of urine samples containing cardiovascular drugs by micellar liquid chromatography with fluorimetric detection , J. Chromatogr. Sci. 37 93-102 (1999). 

Inoue, Y., Kawabata, K. and Suzuki, Y. (1995) Speciation of organotin compounds using inductively-coupled plasma-mass spectrometry with micellar liquid-chromatography. J. Anal. At. Spectrom., 10, 363-266. 

I. Carretero, M. Maldonado, J. J. Lasema, E. Bonet, and R. G. Ramis, Detection of banned drugs in sports by micellar liquid chromatography, Anal. Chem. Acta., 259 203 (1992). 

Esteve-Romero J et al (2010) Tamoxifen monitoring studies in breast cancer patients by micellar liquid chromatography. Anal Bioanal Chem 397 1557-1561... 

Quinones-Torrelo et al. (1999 2001) have demonstrated a correlation of pharmacokinetic properties with results from micellar liquid chromatography. In this method micellar solutions of nonionic surfactants are used as the mobile phase in reverse-phase liquid chromatography. Interactions between the mobile and stationary phases are purported to correspond to the membrane/water interface of biological barriers as hydrophobic, steric, and electronic interactions are important for both. For a series of 18 antihistamines Quinones-Torrelo et al. (2001) showed that both volume of distribution and half-life values were better correlated with retention on these columns than with the classical log K, w descriptor. 

Quinones-Torrelo, C., Sagrado, S., Villaneuva-Camanas, R.M., and Medina-Hemandez, M.J., Development of predictive retention-activity relationship models of tricyclic antidepressants by micellar liquid chromatography, J. Med. Chem., 42, 3154-3162, 1999. 

Micellar liquid chromatography (MLC) is another variation on reversed-phase and ion-pair chromatography. In this mode, the counter ion is a surfactant of high concentration and a long-chain hydrocarbon. Micelles form when the concentration of the surfactant is increased to the point at which aggregation occurs and spherical particles are formed. The hydrophilic parts of the long-chain hydrocarbon are oriented toward the outside of the sphere with the hydrophobic end in the center of the sphere. A mixture of compounds of varying polarity partitions between the... 

Enormous advances and growth in the use of ordered media (that is, surfactant normal and reversed micelles, surfactant vesicles, and cyclodextrins) have occurred in the past decade, particularly in their chromatographic applications. New techniques developed in this field include micellar liquid chromatography, micellar-enhanced ultrafiltration, micellar electrokinetic capillary chromatography, and extraction of bioproducts with reversed micelles techniques previously developed include cyclodextrins as stationary and mobile-phase components in chromatography. The symposium upon which this book was based was the first major symposium devoted to this topic and was organized to present the current state of the art in this rapidly expanding field. 

The first intentional use of surfactants in chromatographic mobile phases at concentrations above the CMC was proposed in 1977 by Armstrong and co-workers (1,86-100). Since the initial reports, the general method, dubbed pseudophase liquid chromatography (PLC) or micellar liquid chromatography (MLC), has moved from the realm of an academic novelty to a demonstrated practical separation technique. 

TABLE VIII. Comparison of the General Effect of Variables on Retention in Reversed-Phase Ion-Pair (RP-IPC) and Micellar Liquid Chromatography (MLC)... 

TABLE X. Viscosity of Commonly Employed Solutions in Micellar Liquid Chromatography... 

Stationary Phase in Micellar Liquid Chromatography Surfactant Adsorption and Interaction with Ionic Solutes... 

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