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Title: Effect of micelles and mixed micelles on efficiency and selectivity of antibiotic-based capillary electrophoretic enantioseparations

Abstract

Vancomycin (an oligophenolic, glycopeptide, macrocyclic antibiotic) has been shown to be a superb chiral selector for anionic and neutral compounds. It was found that adding sodium dodecyl sulfate to the run buffer increased efficiency by over 1 order of magnitude, decreased analysis times, and reversed the elution order of the enantiomers. This allows for control of the retention order as well as the resolution of enantiomers in complex mixtures in a single run. A mechanism is proposed which explains all of the observed effects and is verified experimentally. Since vancomycin is present in both the micelle and in free solution, previously proposed micelle-selector models are, at best, limiting cases. A general equation is derived which can be used to describe all possible interactions, including those with the capillary wall, if needed. Also, it is shown that electrophoretic mobilities and not migration times must be used to calculate binding constants of a solute to the micelle, the chiral selector, or both. Furthermore, it is shown that a neutral marker molecule cannot be used to accurately correct mobilities that have been altered due to changes in solution viscosity. While this work utilizes the practical vancomycin-micelle system, the general conclusions and theory applymore » to most other analogous CE systems as well. 48 refs., 4 figs., 5 tabs.« less

Authors:
;  [1]
  1. Univ. of Missouri, Rolla, MI (United States)
Publication Date:
OSTI Identifier:
83126
DOE Contract Number:
FG02-88ER13819
Resource Type:
Journal Article
Resource Relation:
Journal Name: Analytical Chemistry (Washington); Journal Volume: 67; Journal Issue: 13; Other Information: PBD: 1 Jul 1995
Country of Publication:
United States
Language:
English
Subject:
40 CHEMISTRY; 55 BIOLOGY AND MEDICINE, BASIC STUDIES; 99 MATHEMATICS, COMPUTERS, INFORMATION SCIENCE, MANAGEMENT, LAW, MISCELLANEOUS; ELECTROPHORESIS; USES; ORGANIC COMPOUNDS; AMINO ACIDS; EXPERIMENTAL DATA; MICELLAR SYSTEMS; ELECTRODYNAMICS; CHEMICAL ANALYSIS; ANTIBIOTICS; MATHEMATICAL MODELS; MOBILITY

Citation Formats

Rundlett, K.L., and Armstrong, D.W. Effect of micelles and mixed micelles on efficiency and selectivity of antibiotic-based capillary electrophoretic enantioseparations. United States: N. p., 1995. Web. doi:10.1021/ac00109a030.
Rundlett, K.L., & Armstrong, D.W. Effect of micelles and mixed micelles on efficiency and selectivity of antibiotic-based capillary electrophoretic enantioseparations. United States. doi:10.1021/ac00109a030.
Rundlett, K.L., and Armstrong, D.W. 1995. "Effect of micelles and mixed micelles on efficiency and selectivity of antibiotic-based capillary electrophoretic enantioseparations". United States. doi:10.1021/ac00109a030.
@article{osti_83126,
title = {Effect of micelles and mixed micelles on efficiency and selectivity of antibiotic-based capillary electrophoretic enantioseparations},
author = {Rundlett, K.L. and Armstrong, D.W.},
abstractNote = {Vancomycin (an oligophenolic, glycopeptide, macrocyclic antibiotic) has been shown to be a superb chiral selector for anionic and neutral compounds. It was found that adding sodium dodecyl sulfate to the run buffer increased efficiency by over 1 order of magnitude, decreased analysis times, and reversed the elution order of the enantiomers. This allows for control of the retention order as well as the resolution of enantiomers in complex mixtures in a single run. A mechanism is proposed which explains all of the observed effects and is verified experimentally. Since vancomycin is present in both the micelle and in free solution, previously proposed micelle-selector models are, at best, limiting cases. A general equation is derived which can be used to describe all possible interactions, including those with the capillary wall, if needed. Also, it is shown that electrophoretic mobilities and not migration times must be used to calculate binding constants of a solute to the micelle, the chiral selector, or both. Furthermore, it is shown that a neutral marker molecule cannot be used to accurately correct mobilities that have been altered due to changes in solution viscosity. While this work utilizes the practical vancomycin-micelle system, the general conclusions and theory apply to most other analogous CE systems as well. 48 refs., 4 figs., 5 tabs.},
doi = {10.1021/ac00109a030},
journal = {Analytical Chemistry (Washington)},
number = 13,
volume = 67,
place = {United States},
year = 1995,
month = 7
}
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