title: In-capillary derivatization with (-)-1-(9-fluorenyl)ethyl chloroformate as chiral labeling agent for the electrophoretic separation of amino acids.
abstract: An original micellar electrokinetic chromatography (MEKC) method using in-capillary derivatization with a chiral labeling reagent was developed for the separation of amino acid (AA) derivatives. The potential of (-)-1-(9-fluorenyl)-ethyl chloroformate (FLEC) as in-capillary derivatization agent is described for the first time. Several parameters for in-capillary derivatization and subsequent MEKC separation were systematically investigated using experimental designs. Firstly experimental conditions for in-capillary derivatization were optimized using face-centered central composite design (FCCD). Mixing voltage and time as well as concentration of the labeling solution were investigated. Efficient labeling was achieved by sequential injection of AAs and FLEC labeling solution followed by the application of a voltage of 0.2 kV for 570 s. The background electrolyte (BGE) composition was then optimized in order to achieve selectivity. A FCCD was performed with two factors, namely the sodium dodecyl sulfate (SDS) concentration and the percentage of propan-2-ol (IPA). The separation of 12 pairs of derivatized AA (FLEC-AA) diastereomers was achieved with resolution values comprised between 3 and 20. Furthermore, an efficient derivatization and separation of 29 FLEC-AA derivatives were achieved in a single run using a buffer made up of 40 mM sodium tetraborate, 21 mM SDS and 8.5% IPA. The method was successfully applied to the analysis of spiked artificial cerebrospinal fluid (aCSF) sample.
authors.affiliation: Laboratory of Analytical Pharmaceutical Chemistry, Dept. of Pharmaceutical Sciences, CIRM, University of Liège, CHU, B36, B-4000 Liège 1, Belgium; Laboratory of Chemical, Galenical and Pharmacological Drug Development, Faculty of Pharmacy, University of Monastir, 5000 Monastir, Tunisia; Drug Control National Laboratory, Tunis, Tunisia.
authors.forename: Ines
authors.initials: I
authors.lastname: Fradi
authors.affiliation: Laboratory of Analytical Pharmaceutical Chemistry, Dept. of Pharmaceutical Sciences, CIRM, University of Liège, CHU, B36, B-4000 Liège 1, Belgium.
authors.forename: Elena
authors.initials: E
authors.lastname: Farcas
authors.affiliation: Laboratory of Chemical, Galenical and Pharmacological Drug Development, Faculty of Pharmacy, University of Monastir, 5000 Monastir, Tunisia.
authors.forename: Azza Ben
authors.initials: AB
authors.lastname: Saïd
authors.affiliation: Laboratory of Analytical Pharmaceutical Chemistry, Dept. of Pharmaceutical Sciences, CIRM, University of Liège, CHU, B36, B-4000 Liège 1, Belgium.
authors.forename: Marie-Laure
authors.initials: ML
authors.lastname: Yans
authors.affiliation: Laboratory of Analytical Pharmaceutical Chemistry, Dept. of Pharmaceutical Sciences, CIRM, University of Liège, CHU, B36, B-4000 Liège 1, Belgium.
authors.forename: Caroline
authors.initials: C
authors.lastname: Lamalle
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, University of Amsterdam, The Netherlands.
authors.forename: Govert W
authors.initials: GW
authors.lastname: Somsen
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, University of Amsterdam, The Netherlands.
authors.forename: Amir
authors.initials: A
authors.lastname: Prior
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, University of Amsterdam, The Netherlands.
authors.forename: Gerhardus J
authors.initials: GJ
authors.lastname: de Jong
authors.affiliation: Laboratory of Chemical, Galenical and Pharmacological Drug Development, Faculty of Pharmacy, University of Monastir, 5000 Monastir, Tunisia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Kallel
authors.affiliation: Laboratory of Analytical Pharmaceutical Chemistry, Dept. of Pharmaceutical Sciences, CIRM, University of Liège, CHU, B36, B-4000 Liège 1, Belgium.
authors.forename: Jacques
authors.initials: J
authors.lastname: Crommen
authors.affiliation: Laboratory of Analytical Pharmaceutical Chemistry, Dept. of Pharmaceutical Sciences, CIRM, University of Liège, CHU, B36, B-4000 Liège 1, Belgium.
authors.forename: Anne-Catherine
authors.initials: AC
authors.lastname: Servais
authors.affiliation: Laboratory of Analytical Pharmaceutical Chemistry, Dept. of Pharmaceutical Sciences, CIRM, University of Liège, CHU, B36, B-4000 Liège 1, Belgium. Electronic address: Marianne.fillet@ulg.ac.be.
authors.forename: Marianne
authors.initials: M
authors.lastname: Fillet
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D019075:Electrophoresis, Capillary; D005449:Fluorenes / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D005449:Fluorenes; C052812:1-(9-fluorenyl)ethyl chloroformate
keywords: Amino acids; Chiral capillary electrophoresis; FLEC; In-capillary derivatization