References of "Chiap, Patrice"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailAutomated determination of pirlindole enantiomers in plasma by on-line coupling of a pre-column packed with restricted access material to a chiral liquid chromatographic column
Chiap, Patrice ULg; Ceccato, Attilio ULg; Gora, R. et al

in Journal of Pharmaceutical & Biomedical Analysis (2002), 27(3-4), 447-455

A fully automated liquid chromatographic method has been developed for the determination of the enantiomers of pirlindole, an antidepressant drug, in human plasma. The method is based on the use of a pre ... [more ▼]

A fully automated liquid chromatographic method has been developed for the determination of the enantiomers of pirlindole, an antidepressant drug, in human plasma. The method is based on the use of a pre-column packed with restricted access material (RAM) (LiChrospher ADS RP-4) for sample clean-up coupled to a column containing a cellulose tris-(3,5-dimethylphenylcarbamate) based chiral stationary phase (Chiralcel OD-R) for the separation and quantitative analysis of pirlindole enantiomers. A 50-microl plasma volume was injected directly onto the pre-column using a mixture of phosphate buffer (pH 5.0) and methanol (97:3; v/v) as washing liquid. By rotation of a switching valve, the analytes were then eluted in the back-flush mode with the LC mobile phase. A complete separation of pirlindole enantiomers was obtained in 22 min on the Chiralcel OD-R column, using a mobile phase made of a mixture of phosphate buffer (pH 5.0) containing 50 mM sodium perchlorate and acetonitrile (65:35; v/v). The flow-rate was 0.6 ml/min and the analytes were detected fluorometrically using 295 and 340 nm as excitation and emission wavelengths, respectively. The method was then validated and was found to be linear in the 2.5-200 ng/ml range. The limit of detection was lower than 1 ng/ml. Repeatability and intermediate precision at a concentration of 50 ng/ml were about 1.5 and 3.5%, respectively. [less ▲]

Detailed reference viewed: 23 (0 ULg)
Peer Reviewed
See detailStatistical analysis of the validation results: diagnostic or decision tools
Hubert, Philippe ULg; Chiap, Patrice ULg; Dormal, C. et al

Conference (2002)

Detailed reference viewed: 17 (1 ULg)
Full Text
Peer Reviewed
See detailOn-Line Coupling of Partial Filling-Capillary Zone Electrophoresis with Mass Spectrometry for the Separation of Clenbuterol Enantiomers
Toussaint, B.; Palmer, M.; Chiap, Patrice ULg et al

in Electrophoresis (2001), 22(7), 1363-72

The on-line coupling of capillary zone electrophoresis with mass spectrometry (CZE-MS) for the separation of enantiomers is hampered by the presence of nonvolatile chiral selectors such as cyclodextrins ... [more ▼]

The on-line coupling of capillary zone electrophoresis with mass spectrometry (CZE-MS) for the separation of enantiomers is hampered by the presence of nonvolatile chiral selectors such as cyclodextrins in the separation buffer. This problem can be overcome by use of the partial filling technique where only a part of the capillary is filled with the separation buffer containing chiral selectors. Since the electroosmotic flow is almost completely suppressed at acidic pH, that dimethyl-beta-cyclodextrin is neutral, no free cyclodextrin would reach the MS detector when using a partially filled capillary. By this method, clenbuterol enantiomers were successfully resolved and separated from salbutamol (internal standard) in aqueous solution and in plasma samples. A solid-phase extraction (SPE) was used for the preparation of plasma samples before analysis. [less ▲]

Detailed reference viewed: 12 (0 ULg)
Full Text
Peer Reviewed
See detailDevelopment and Validation of an Automated Method for the Liquid Chromatographic Determination of Sotalol in Plasma Using Dialysis and Trace Enrichment on a Cation-Exchange Pre-Column as on-Line Sample Preparation
Chiap, Patrice ULg; Ceccato, Attilio ULg; Miralles Buraglia, B. et al

in Journal of Pharmaceutical & Biomedical Analysis (2001), 24(5-6), 801-14

A fully automated method for the determination of sotalol in human plasma was developed, involving dialysis through a cellulose acetate membrane, clean-up and enrichment of the dialysate on a strong ... [more ▼]

A fully automated method for the determination of sotalol in human plasma was developed, involving dialysis through a cellulose acetate membrane, clean-up and enrichment of the dialysate on a strong cation-exchange pre-column and subsequent liquid chromatographic (LC) analysis with UV detection. All sample handling operations were carried out by means of an ASTED system. Before starting dialysis, the trace enrichment column (TEC) was conditioned. The plasma sample, to which the internal standard (atenolol) was automatically added, was then loaded in the donor channel and was kept static while the dialysis liquid, consisting of 0.017 M acetic acid, was passed through the acceptor channel in successive pulses. After each pulse, the dialysate was dispensed onto the TEC. When dialysis was discontinued, the analytes were eluted from the TEC by the LC mobile phase by rotation of a switching valve and transferred to the analytical column packed with octyl silica. The LC mobile phase was a mixture of methanol and pH 7.0 phosphate buffer containing 1-octanesulfonate at a concentration of 7.5 x 10(-4) M (19:81; v/v). The UV detection was performed at 230 nm. The influence of several parameters of the dialysis and trace enrichment processes on analyte recovery and method selectivity was investigated. The method was then validated. The mean absolute recovery for sotalol was about 60%. The limit of quantitation was 25 ng/ml and R.S.D. for repeatability and intermediate precision obtained at a concentration level of 50 ng/ml were 4.3 and 5.8%, respectively. [less ▲]

Detailed reference viewed: 24 (1 ULg)