title: Three-phase liquid-phase microextraction of weakly basic drugs from whole blood.
abstract: The behaviour of weak basic analytes in liquid-phase microextraction (LPME) and the optimisation of parameters in whole blood are described. Benzodiazepines and non-benzodiazepine drugs were chosen as model substances. Liquid-phase microextraction based on disposable polypropylene hollow fibres was used in the three-phase extraction of five weak bases from whole blood. The sample work up with the liquid-phase microextraction technique can be impeded by low recovery due to incomplete trapping in the acceptor phase of weakly basic drugs and the complexity of the whole blood matrix. Different parameters related to this problem were experimentally studied. Additionally the stability of the analytes was examined because of low pH in the acceptor phase. The investigation resulted in optimised LPME conditions for the extraction of weak bases from whole blood. The parameters limiting the recovery were evaluated.
authors: School of Pharmacy, University of Oslo, P.O. Box 1068 Blindern, 0136 Oslo, Norway.
authors: Hege Grefslie
authors: HG
authors: Ugland
authors: Mette
authors: M
authors: Krogh
authors: Léon
authors: L
authors: Reubsaet
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D004364:Pharmaceutical Preparations / Q000097:blood*; D012015:Reference Standards; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D004364:Pharmaceutical Preparations