Showing results 1 to 20 of 43
  Determination of Six Water-Soluble Vitamins in a Pharmaceutical Formulation by Capillary ElectrophoresisFotsing, Lucas  ; Fillet, Marianne ; et alin Journal of Pharmaceutical & Biomedical Analysis (1997), 15(8), 1113-23 A method was developed for the quantitative analysis of six water-soluble vitamins (thiamine, nicotinamide, riboflavine, pyridoxine, ascorbic acid and pantothenic acid) in a pharmaceutical formulation ... [more ▼] A method was developed for the quantitative analysis of six water-soluble vitamins (thiamine, nicotinamide, riboflavine, pyridoxine, ascorbic acid and pantothenic acid) in a pharmaceutical formulation, using free solution capillary zone electrophoresis (CZE) in uncoated fused silica capillaries and UV detection. The influence of different parameters, such as the nature of the buffer anionic component and buffer concentration on the CZE separation of vitamins was investigated using four vitamins of the B group as model compounds. A good compromise between resolution, analysis time and analyte stability was obtained by use of a 50 mM borax buffer of pH 8.5. This CZE method was found to be very useful for the separation of more complex samples, a mixture of ten water-soluble vitamins being completely resolved in about 10 min. However, cyanocobalamine could not be separated from nicotinamide in this CZE system, the two compounds being in uncharged form at the pH used. These two compounds could easily be resolved by micellar electrokinetic chromatography (MEKC), the anionic surfactant dodecylsulfate being added to the running buffer at 25 mM concentration. In the pharmaceutical formulation, some excipients were found to be adsorbed to the capillary surface, giving rise to a progressive decrease of the electroosmotic flow and consequently to a simultaneous increase of analyte migration times. A capillary wash with sodium hydroxide had to be made between successive runs in order to minimize these effects. Good results with respect to linearity, precision and accuracy were obtained in the concentration range studied for the six vitamins, using nicotinic acid as internal standard. [less ▲] Detailed reference viewed: 67 (1 ULg)The use of mixtures of anaionic and uncharged cyclodextrins for the enantiomeric separation of acidic drugs by capillary electrophoresisFillet, Marianne ; ; et alPoster (1997) Detailed reference viewed: 3 (0 ULg)Enantiomeric separation of basic drugs by CZE using charged and uncharged cyclodextrins as chiral selectorsFillet, Marianne ; ; Ceccato, Attilio et alPoster (1997) Detailed reference viewed: 3 (0 ULg)Resolution Improvement by Use of Carboxymethyl-Beta-Cyclodextrin as Chiral Additive for the Enantiomeric Separation of Basic Drugs by Capillary ElectrophoresisFillet, Marianne ; ; Hubert, Philippe et alin Journal of Pharmaceutical & Biomedical Analysis (1996), 14(8-10), 1107-14 Three beta-cyclodextrin derivatives--carboxymethyl-, dimethyl- and hydroxypropyl-beta-cyclodextrin--were tested as chiral selectors for the enantioseparation of seven basic drugs in free solution ... [more ▼] Three beta-cyclodextrin derivatives--carboxymethyl-, dimethyl- and hydroxypropyl-beta-cyclodextrin--were tested as chiral selectors for the enantioseparation of seven basic drugs in free solution capillary electrophoresis, using buffers made of 100 mM phosphoric acid adjusted to pH 3.0 with triethanolamine in fused silica capillaries thermostatted at 15 degrees C. The best results with respect to chiral resolution were obtained with carboxymethyl-beta-cyclodextrin (CMCD): the enantiomers of all compounds examined were completely resolved with this beta-cyclodextrin derivative. The influence of the CMCD concentration on the migration times, the apparent electrophoretic mobility difference and the resolution of the drug enantiomers was investigated thoroughly. Particularly impressive resolution values, up to 23.7, were obtained for several compounds in these capillary electrophoretic systems, using CMCD in the 5-15 mM concentration range. [less ▲] Detailed reference viewed: 18 (1 ULg)Enhanced resolution in the capillary electrophoresis of drug enantiomers by use of charged cyclodextrin derivatives and dynamically or permanently coated capillariesFillet, Marianne ; ; et alConference (1996) Detailed reference viewed: 1 (1 ULg)Enantiomeric separation of acidic drugs by capillary electrophoresis using mixtures of anionic and uncharged cyclodextrins as chiral additivesFillet, Marianne ; ; et alConference (1996) Detailed reference viewed: 4 (1 ULg)Applications of cyclodextrin mediated capillary electrophoresis to the chiral analysis of drugs and related compoundsCrommen, Jacques ; Fillet, Marianne ; et alConference (1996) Detailed reference viewed: 2 (1 ULg)Chiral separations of drugs by capillary electrophoresis using neutral and charged cyclodextrin derivativesCrommen, Jacques ; Fillet, Marianne ; et alConference (1996) Detailed reference viewed: 2 (1 ULg)Determination of water-soluble vitamins by capillary zone electrophoresisFotsing, Lucas ; ; Fillet, Marianne et alin Journal de Pharmacie de Belgique (1996), 51 Detailed reference viewed: 3 (2 ULg)Enantiomeric separation of acidic and basic drugs by capillary electrophoresis using neutral and anionic cyclodextrinsFillet, Marianne ; ; et alin Journal de Pharmacie de Belgique (1996), 51 Detailed reference viewed: 4 (1 ULg)Influence of organic modifiers and cyclodextrins on the CZE separation of non-steroidal anti-inflammatory drugs; Fillet, Marianne ; Hubert, Philippe et alPoster (1996) Detailed reference viewed: 1 (1 ULg)Improvement of a chiral resolution in capillary zone electrophoresis by use of cyclodextrin additives; Fillet, Marianne ; Hubert, Philippe et alConference (1995) Detailed reference viewed: 1 (1 ULg)CZE separation of basic and acidic drug by use of cyclodextrin additives; Fillet, Marianne ; Fotsing, Lucas et alPoster (1995) Detailed reference viewed: 5 (1 ULg)Enantiomeric separations by capillary electrophoresis applications in pharmaceutical, biomedical and environmental analysisCrommen, Jacques ; Fillet, Marianne ; et alConference (1995) Detailed reference viewed: 3 (1 ULg)Automated determination of camazepam in human plasma by solid phase extraction coupled to HPLCHubert, Philippe ; Chiap, Patrice ; Ceccato, Attilio et alin Journal de Pharmacie de Belgique (1995), 50 Detailed reference viewed: 2 (2 ULg)Enantiomeric separaiton of sotalol and other B-blockers on a chiral-AGP column using aliphatic carboxylic acids as ionic modifiersCeccato, Attilio ; Hubert, Philippe ; et alin Journal de Pharmacie de Belgique (1995), 50 Detailed reference viewed: 2 (1 ULg)Enantiomeric separation of basic drugs by cyclodextrin modified capillary electrophoresis using poly(vinyl alcohol) coated fused silica capillariesFillet, Marianne ; ; et alin Journal de Pharmacie de Belgique (1995), 50 Detailed reference viewed: 7 (2 ULg)Comparison of Ce and LC methods for the determination of B vitamins in pharmaceutical dosage formsFotsing, Lucas ; Fillet, Marianne ; et alin Journal de Pharmacie de Belgique (1995), 50 Detailed reference viewed: 2 (1 ULg)Influence of organic modifiers and complexing agents on the separation of non-steroidal anti-inflammatory drugs by capillary zone electrophoresis; Fillet, Marianne ; Fotsing, Lucas et alin Journal de Pharmacie de Belgique (1995), 50 Detailed reference viewed: 3 (1 ULg)Enantiomeric separations of basic drugs by capillary electrophoresis using derivatized cyclodextrins and dynamically or permanently modified capillariesFillet, Marianne ; ; et alPoster (1995) Detailed reference viewed: 4 (1 ULg) |
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