Micellar HPLC

Figure 15.4 Separation of mixtures of beta-blockers by using micellar HPLC, employing the following mobile phases (a) 0.12M SDS, 5% propanol, 0.5% tiiethylamine (b) 0.06 M SDS, 15% propanol (c) 0.1 IM SDS, 8% propanol. Adapted from Journal of Chromatographic Science, 37, S. Carda-Broch et al., Analysis of urine samples containing cardiovascular drugs by micellor liquid chromatography with fluorimetric detection , pp. 93-102, 1999, with permission from Preston Publications, a division of Preston Industries, Inc.

Micellar HPLC with micellar mobile phases containing sodium dodecyl sulfate, with and without different alcohols, has been used to determine diuretics in pharmaceuticals [185]. 

Although a great variety of analytical techniques have been applied to the simultaneous determination of methylxanthines in various matrices, HPLC is the one most frequently used nowadays. Most of the methods are based on reversed-phase HPLC, using ACN, MeOH, or THF in acetate or phosphate buffer as mobile phase and UV spectrophotometric detection (256 -270). Some RP-HPLC methods were proposed in combination with solid-surface room-temperature phosphori-metric detection (271), mass spectrometry (272), or amperometric (273) detection. The separation can also be achieved by RP ion-pair or ion-interaction HPLC (274-277) or micellar HPLC (278). In contrast, in recent years few normal-phase HPLC methods (279) were reported (see Table 5). 

Since the evaluation of this parameter is very important, it was also measured using the micellar HPLC technique (9), which allows a better estimation of the partition coefficients in the presence of quite high concentrations of surfactant. The chromatographic parameter P was measured for each ligand as a function of surfactant concentration, according to Equation 2 ... 

M. Lin, N. Wu and J.H. Aiken, Micellar HPLC Separation of Serum Bilirubin Species with Direct Sample Injection, J. Liq. Chromatogr., 18 1219 (1995). 

M.L. Marina, S. Vera and A.R. Rodriguez, Determination of the Micelle-Solute Association Constants of some Benzene and Naphthalene Derivatives by Micellar HPLC, Chromatographia, 28 379 (1989). 

M. A. Strege and A.L. Lagu, Analysis of Recombinant Human Growth Hormone in Escherichia Coli Fermentation Broth by Micellar HPLC, J. Chromatogr. A, 705 155 (1995). 

M.C. Garcia Alvarez-Coque, E.F. Simo Alfonso, G. Ramis Ramos and J.S. Esteve Komsto, Micellar HPLC Determination of Sulfonamides in Pharmaceuticals after Azo Dye Precolumn Derivatization, J. Pharm. Biomed. Anal, 13 237 (1995). 

Coque, Determination of Amino Acids by Micellar HPLC and Precolumn Derivatization with o-Phthalaldehyde and N-Acetyl-L-... 

T.A. Biemer, Simultaneous Analysis of Acetaminophen, Pseudoephedrine Hydrochloride and Chlorpheniramine Maleate in a Cold Tablet using an Isocratic, Mixed Micellar HPLC Mobile Phase, J Chromatogr., 410 206 (1987). 

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