title: Field-amplified on-line sample stacking for simultaneous enantioseparation and determination of some beta-blockers using capillary electrophoresis.
abstract: A capillary electrophoresis method using carboxymethyl-beta-cyclodextrin as the chiral selector and mixture of methanol and ethanol as the organic additive was successfully developed for the simultaneous enantioseparation and determination of six beta-blockers, namely, carteolol, atenolol, sotalol, metoprolol, esmolol and propranolol in this paper. The most suitable running buffer for enantioseparation was found to be the solution of 20 mmol/L NaH(2)PO(4)-Na(2)HOP(4) (pH 5.5) containing 1.5% w/v carboxymethyl-beta-cyclodextrin, 5% v/v methanol and 5% v/v ethanol. Furthermore, field-amplified sample injection as an on-line sample stacking method was developed in order to increase the detection sensitivity. The experimental conditions for both simultaneous enantioseparation and the field-amplified sample injection method had been investigated in detail. Under the optimum conditions, the detection limits (defined as S/N=3) of this method were 0.01, 0.05, 0.05, 0.05, 0.05 and 0.5 microg /mL for (+/-) carteolol, (+/-) atenolol, (+/-) sotalol, (+/-) metoprolol, (+/-) esmolol and (+/-) propranolol, respectively, which were much lower than those of the conventional methods. The enhancement factors were greatly improved by 25-fold for the enantiomers of the beta-blockers except five-fold for (+/-) propranolol. Eventually, the proposed method has been applied for the analysis of human serum sample.
authors.affiliation: Fuzhou University, Fuzhou, Fujian, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Huang
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Lin
authors.forename: Lishuang
authors.initials: L
authors.lastname: Yu
authors.forename: Liangjun
authors.initials: L
authors.lastname: Xu
authors.forename: Guonan
authors.initials: G
authors.lastname: Chen
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000097:blood / Q000302:isolation & purification*; D019075:Electrophoresis, Capillary / Q000379:methods*; D006801:Humans; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
chemical_list: D000319:Adrenergic beta-Antagonists