title: Determination of cabergoline and L-dopa in human plasma using liquid chromatography-tandem mass spectrometry.
abstract: We determined cabergoline and L-dopa in human plasma using liquid chromatography-mass spectrometry with tandem mass spectrometry (LC-MS-MS). The deproteinized plasma samples with organic solvent or acid were analyzed directly by reversed-phase liquid chromatography. Using multiple reaction monitoring (MRM, product ions m/z 381 of m/z 452 for cabergoline and m/z 152 of m/z 198 for L-dopa) on LC-MS-MS with electrospray ionization (ESI), cabergoline and L-dopa in human plasma were determined. Calibration curves of the method showed a good linearity in the range 5-250 pg/ml for cabergoline and 1-200 ng/ml for L-dopa, respectively. The limit of determination was estimated to be approximately 2 pg/ml for cabergoline and approximately 0.1 ng/ml for L-dopa, respectively. The method was applied to the analysis of cabergoline and L-dopa in plasma samples from patients treated with these drugs. The precision of analysis showed coefficients of variation ranging from 3.8% to 10.5% at cabergoline concentration of 13.8-26.2 pg/ml and from 2.9% to 8.9% at an L-dopa concentration of 302.5-522.1 ng/ml in patient plasma. As a result, the procedure proved to be very suitable for routine analysis.
authors.affiliation: Laboratory of Biochemical Toxicology, Faculty of Pharmaceutical Sciences and High Technology Research Center, Kobe Gakuin University, Ikawadanicho, Nishi-ku, Kobe 651-2180, Japan. igarashi@pharm.kobegakuin.ac.jp
authors.forename: Kazuo
authors.initials: K
authors.lastname: Igarashi
authors.forename: Koichiro
authors.initials: K
authors.lastname: Hotta
authors.forename: Fumiyo
authors.initials: F
authors.lastname: Kasuya
authors.forename: Kazuo
authors.initials: K
authors.lastname: Abe
authors.forename: Saburo
authors.initials: S
authors.lastname: Sakoda
mesh_terms: D000328:Adult; D000077465:Cabergoline; D016022:Case-Control Studies; D002853:Chromatography, Liquid / Q000379:methods*; D018491:Dopamine Agonists / Q000097:blood* / Q000627:therapeutic use; D004873:Ergolines / Q000097:blood* / Q000627:therapeutic use; D006801:Humans; D007980:Levodopa / Q000097:blood* / Q000627:therapeutic use; D008875:Middle Aged; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000097:blood / Q000188:drug therapy; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D018491:Dopamine Agonists; D004873:Ergolines; D007980:Levodopa; D000077465:Cabergoline