Capillary electrophoretic enantiomeric separations using the glycopeptide antibiotic, teicoplanin

Abstract

Teicoplanin is the third in a series of macrocyclic glycopeptide antibiotics that has been evaluated as a chiral selector in capillary electrophoresis (CE). It was used to resolve over 100 anionic racemates at low selector concentrations. Like the other related glycopeptide antibiotics, its enantioselectivity tends to be opposite to that of the ansa‐type antibiotics which prefers cationic compounds, particularly amines. Factors that affect teicoplanin‐based enantioseparations include the selector concentration, pH, and the concentration of the organic modifier. The temperature and the nature and strength of the buffer are also known‐to affect the stability of the chiral selector as well as the enantioseparation. Teicoplanin exhibited some features that were not noted with the other glycopeptide antibiotics. For example, it aggregates (forms micelles) in aqueous solutions and this influences its enantioselectivity. Unlike the other studied glycopeptides, teicoplanin precipitates in alcohol‐water mixtures. It also binds less to the capillary wall than vancomycin as evidenced by the faster electroosmotic flow velocity. The micellization of teicoplanin is pH dependent so that the effect of pH on enantiorecognition is more complex for teicoplanin than for other chiral selectors. Also it is shown that the simple model proposed to explain the role of organic modifiers in cyclodextrin‐based CE enantioseparations may not apply to these and other systems. © 1996 Wiley‐Liss, Inc.

Teicoplanin‐Based Enantioselective, Potentiometric Membrane Electrodes for the Determination of R‐Baclofen in Pharmaceutical Formulations

“…It is clear that modification of teicoplanin by acetonitrile leads to slight improvement of the electrode's enantioselective properties. These results are in good concordance with ones obtained by Rundlett et al [16] and Tesarˇova et al [21] when teicoplaninbased systems were used for capillary electrophoretic and chromatographic separations. These results also prove that both electrodes can be used for R-baclofen enantioanalysis.…”

“…Organic modifiers enhance the electrostatic interaction forces required for chiral recognition. Thus, the results of capillary electrophoretic enantiomeric separations performed by Rundlett et al [16] showed that the addition of low concentrations of acetonitrile improves the enantioselective properties of teicoplanin-based systems. Tesarova et al [21] also observed the improvement of teicoplanin's enantioselective properties during high-performance liquid chromatographic and capillary electrophoretic separations of amino acids enantiomers.…”

Chiral Separations in Capillary Electrophoresis

“…The effect of the addition of methoxyethanol was substantial in the optimization of the separation conditions with A53312B. 207 The studies [203][204][205][206][207][208] are highly informative and inspirational as far as the enantioselective capabilities of the glycopeptide macrocyclic antibiotics to various compound types are concerned.…”

Development and validation of a direct enantiomeric separation of pregabalin to support isolated perfused rat kidney studies☆

“…Macrocyclic glycopeptide-based stationary phases were introduced in 1994 [20] and have been used to separate an array of enantiomeric compounds that includes amino acids [21][22][23][24][25][26][27][28][29]. The macrocyclic glycopeptide provides a number of chiral centers, binding pockets, sites of aromaticity, and hydrogen donors/acceptors enabling a variety of interactions such as hydrophobic, hydrogen bonding, dipole, -, steric repulsion, and ionic.…”