title: Determination of alpha-methyldopa in human plasma by validated high-performance liquid chromatography with fluorescence detection.
abstract: A sensitive reversed-phase gradient elution high-performance liquid chromatographic method with fluorescence detection has been developed for the determination of alpha-methyldopa (AMD) in human plasma. Separation of the investigated compound and the 3,4-dihydroxyphenylalanine (DOPA) internal standard was achieved on a Nucleosil 7 C18 column with a 5 mM heptanesulphonic acid sodium salt containing 0.05 M potassium dihydrogenphosphate (pH 3.2)-acetonitrile mobile phase. The composition of the mobile phase was changed according to a linear gradient time program. Detection was performed at 270 nm fluorimetric excitation and 320 nm emission. The compounds were isolated from plasma by Bond-Elut C18 solid-phase extraction. The limit of quantitation was found to be 10 ng/ml plasma. The assay was validated with respect to accuracy, precision and system suitability. All validated parameters were found to be within the 20% required limits. On the basis of the sensitivity, linearity and validation parameters the developed analytical method was found to be suitable for application in a bioequivalency study.
authors.affiliation: Department of I. Medicine, Haynal Imre University of Medical Sciences, Budapest, Hungary.
authors.forename: K
authors.initials: K
authors.lastname: Róna
authors.forename: K
authors.initials: K
authors.lastname: Ary
authors.forename: B
authors.initials: B
authors.lastname: Gachályi
authors.forename: I
authors.initials: I
authors.lastname: Klebovich
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004295:Dihydroxyphenylalanine; D006801:Humans; D007202:Indicators and Reagents; D008750:Methyldopa / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence
chemical_list: D007202:Indicators and Reagents; D008750:Methyldopa; D004295:Dihydroxyphenylalanine