Lovgren U.,Experimental Medicine Bioanalysis |
Johansson S.,Experimental Medicine Bioanalysis |
Jensen L.S.,Experimental Medicine Bioanalysis |
Ekstrom C.,Experimental Medicine Bioanalysis |
Carlshaf A.,Experimental Medicine Bioanalysis
Journal of Pharmaceutical and Biomedical Analysis | Year: 2010
Plasma concentrations after administration of peptide drugs are often low due to the high potency often seen with this class of compounds. In this work a bioanalytical method based on coupled column liquid chromatography-tandem mass spectrometry (LC-MS/MS) is presented for quantification of a peptide drug, FE 202158, under clinical development. A volume of 0.5ml human plasma is solid phase extracted on a weak cationic exchanger. After evaporation of the solvent to dryness, the reconstituted sample is injected into a coupled column liquid chromatography system. A heart-cut from the initial column, a cyano column, is trapped on a C 4 column and thereafter injected into a microbore C 18 column. For the detection a triple quadrupole mass spectrometer, equipped with a TurboIonSpray interface working in positive ion mode, is used. The design of the system is described and the gain in sensitivity and selectivity, compared to a conventional system, is discussed. Data from validation of the bioanalytical method are presented. For human plasma samples a lower limit of quantification (LLOQ) of 5.00pg/ml (=4.77pmol/l) was achieved. The inter-assay precision was less than 11% and bias was within ±4% over the whole validated range of 5.00-860pg/ml. © 2010 Elsevier B.V.