title: One-step extraction of polar drugs from plasma by parallel artificial liquid membrane extraction.
abstract: The new microextraction technique named parallel artificial liquid membrane extraction (PALME) was introduced as an alternative approach to liquid-liquid extraction of charged analytes from aqueous samples. The concept is based on extraction of analytes across a supported liquid membrane sustained in the pores of a thin polymeric membrane, a well-known extraction principle also used in hollow fiber liquid-phase microextraction (HF-LPME). However, the new PALME technique offers a more user-friendly setup in which the supported liquid membrane is incorporated in a 96 well plate system. Thus, high-throughput is achievable, in addition to the green chemistry offered by using PALME. The consumption of organic solvent is minimized to 3-5μL per sample. With a sample volume of 250μL and acceptor solution volume of 50μL, a maximal enrichment factor of five is achievable. Based on these parameters, a new method for extraction of polar basic drugs was developed in the present work. The basic drugs hydralazine, ephedrine, metaraminol, salbutamol, and cimetidine were used as model analytes, and were extracted from alkalized human plasma into an aqueous solution via the supported liquid membrane. The extraction was promoted by a carrier dissolved in the membrane, creating a temporary ion-pair complex between the hydrophilic drug and the carrier. As the model analytes were extracted directly into an aqueous solution, there was no need for evaporation of the extract before injection into LC-MS. Hence, the sample preparation is performed in one step. With optimized conditions, the extraction recoveries were in the range 50-89% from human plasma after 45min extraction. The data from the method evaluation were satisfactory and in line with current guidelines, and revealed an extraction method with substantial potential for high throughput bioanalysis of polar basic drugs.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Charles University in Prague, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
authors.forename: Veronika
authors.initials: V
authors.lastname: Pilařová
authors.affiliation: School of Pharmacy, University of Oslo, Norway.
authors.forename: Mumtaz
authors.initials: M
authors.lastname: Sultani
authors.affiliation: School of Pharmacy, University of Oslo, Norway.
authors.forename: Kristine Skoglund
authors.initials: KS
authors.lastname: Ask
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Charles University in Prague, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Nováková
authors.affiliation: School of Pharmacy, University of Oslo, Norway; Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: Stig
authors.initials: S
authors.lastname: Pedersen-Bjergaard
authors.affiliation: School of Pharmacy, University of Oslo, Norway. Electronic address: astrid.gjelstad@farmasi.uio.no.
authors.forename: Astrid
authors.initials: A
authors.lastname: Gjelstad
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D016014:Linear Models; D059625:Liquid-Liquid Extraction / Q000379:methods*; D013058:Mass Spectrometry / Q000379:methods*; D008567:Membranes, Artificial; D004364:Pharmaceutical Preparations / Q000097:blood* / Q000737:chemistry / Q000302:isolation & purification*; D015203:Reproducibility of Results
chemical_list: D008567:Membranes, Artificial; D004364:Pharmaceutical Preparations
keywords: Carrier-mediated transport; Microextraction; PALME; Parallel artificial liquid membrane extraction; Supported liquid membrane