Determination of α-methyldopa in human plasma by validated high-performance liquid chromatography with fluorescence detection

• Published in: Journal of Chromatography A 1996-04, Vol.730 (1), p.125-131
• Main Authors: Róna, K., Ary, K., Gachályi, B., Klebovich, I.
• Format: Article
• Language: English
• Subjects: Chromatography, High Pressure Liquid - methods; Dihydroxyphenylalanine; DOPA; Humans; Indicators and Reagents; Methyldopa; Methyldopa - blood; Reproducibility of Results; Sensitivity and Specificity; Spectrometry, Fluorescence
• ISSN: 0021-9673
• DOI: 10.1016/0021-9673(95)01227-3

A sensitive reversed-phase gradient elution high-performance liquid chromatographic method with fluorescence detection has been developed for the determination of α-methyldopa (AMD) in human plasma. Separation of the investigated compound and the 3,4-dihydroxyphenylalanine (DOPA) internal standard was achieved on a Nucleosil 7 C 18 column with a 5 m M 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 C 18 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.