Determination of trace enantiomeric impurities in chiral compounds by capillary electrophoresis with uncoated, cationic, anionic and neutral surface modified capillaries

Assi, K.H.; Abushoffa, A.; Altria, Kevin D.; Clark, Brian J.

doi:10.1016/s0021-9673(98)00245-3

Cited by 31 publications

(16 citation statements)

References 15 publications

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“…However, separations of low concentrations of basic drugs often suffer from poor accuracy and precision [42] due to inconsistent EOF and analyte adsorption onto the capillary wall. Coatings such as polyamines have yielded better migration time reproducibility and detection limits for basic drugs [43]. Figure 6 shows the separation of b-blocker drugs, propranolol, and metoprolol, using a 2C 18 DAB-coated capillary in aqueous and methanolic buffers at pH 3.0.…”

Section: Separation Of Basic Drugsmentioning

confidence: 99%

Semipermanent capillary coatings in mixed organic–water solvents for CE

2007

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This report describes the creation of semipermanent capillary coatings that are compatible with organic-water solvent systems in CE. The coatings are created by simply rinsing the fused-silica capillary with long double-chain cationic surfactants, such as dimethyl-ditetradecyl ammonium bromide (2C(14)DAB), dihexadecyldimethyl ammonium bromide (2C(16)DAB), and dimethyldioctadecyl ammonium bromide (2C(18)DAB). These surfactants generate semipermanent bilayer coatings on the capillary surface, which display a high degree of stability in buffers containing up to 60% v/v of organic solvents, such as methanol and ACN. The coating stability increases with increasing hydrophobicity of the surfactant, i.e., with increasing chain length. For instance, the EOF changes by only 1.2% in a 2C(18)DAB-coated capillary after 130 capillary volumes of rinsing with 60% v/v methanol containing buffer. The bilayer coatings allow separations to be performed without the need to regenerate the coating between runs or to maintain the EOF modifier in the run buffer. Rapid separations (<2 min) of anions and basic drugs with migration time reproducibility of less than 0.5% RSD and efficiencies of 0.4-0.6 million plates/m are obtained. In addition, selectivity changes for small anions and cationic drugs are also observed when the organic solvent content is adjusted.

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Section: Separation Of Basic Drugsmentioning

confidence: 99%

Semipermanent capillary coatings in mixed organic–water solvents for CE

2007

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“…The enantioseparation of W F by CE has been reported in a number of papers but [21 35], the enantiomer migration order has been studied in only a few of them [31,35]. Recently, Fillet et al reported the enantioseparation of W F with dual CD systems combining neutral and charged CDs [11,12].…”

Section: Introductionmentioning

confidence: 99%

Enantioseparation of warfarin by capillary electrophoresis with UV and LIF detection using single and dual cyclodextrin type chiral selectors

et al. 2001

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SummaryThe enantioseparation of warfarin (WF) by capillary electrophoresis (CE) has been studied using various cyclodextrins (CD) such as native a, I 3 and y-CD, several neutral and randomly and selectively substituted charged CD derivatives. The enantiomer migration order of WF was determined with individual CDs. Various, CD combinations were used in order to enhance or diminish the separation factor in a designed way.

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“…The chiral separation of a range of basic drugs was significantly improved using a C 8 -coated capillary when compared to use of an uncoated capillary, for example [12]. Optimisation of a method [13] for the chiral purity testing of tryptophan using a positively charged polyamine-coated capillary allowed detection limits of 0.03% m/m to be achieved. A positively charged coated capillary has also been used in conjunction…”

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confidence: 99%