title: Micro-CLC as an interface between SLM extraction and CZE for enhancement of sensitivity and selectivity in bioanalysis of drugs.
abstract: This work demonstrates the high selectivity and sensitivity obtainable in bioanalysis using the supported liquid membrane (SLM) technique coupled on line with capillary zone electrophoresis (CZE) through a micro-column liquid chromatography (CLC) interface. The system utilizes two selective, sequential enrichment steps before the third analyte focusing and separation step with double-stacking CZE. The enantiomers of bambuterol in human plasma can be concentrated about 40,000 times (approx. 6 times by the SLM treatment, approx. 17 times by micro-CLC focusing, and approx. 400 times by double-stacking CZE) on their way through the system, and extremely high selectivity is obtained. Determinations in the subnanomolar region are achievable for the enantiomers despite relatively weak UV absorbance. Good performance of the entire procedure is demonstrated and a method to increase the sample throughput is presented.
authors.affiliation: Department of Analytical Chemistry, Lund University, Sweden.
authors.forename: S
authors.initials: S
authors.lastname: Pálmarsdóttir
authors.forename: L
authors.initials: L
authors.lastname: Mathiasson
authors.forename: J A
authors.initials: JA
authors.lastname: Jönsson
authors.forename: L E
authors.initials: LE
authors.lastname: Edholm
mesh_terms: D001993:Bronchodilator Agents / Q000097:blood*; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods; D006801:Humans; D007202:Indicators and Reagents; D008832:Microchemistry; D010830:Physostigmine / Q000097:blood* / Q000302:isolation & purification; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism; D013726:Terbutaline / Q000031:analogs & derivatives* / Q000097:blood / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D001993:Bronchodilator Agents; D007202:Indicators and Reagents; D010830:Physostigmine; D013726:Terbutaline; C047766:bambuterol