Determination of valproic acid in human serum by high-performance liquid chromatography with fluorescence detection.
A simple and highly sensitive high-performance liquid chromatographic method is described for the determination of valproic acid in human serum. The method is based on the direct derivatization of serum sample with 6,7-methylenedioxy-1-methyl-2-oxo-1,2-dihydroquinoxaline-3-ylpr opionohydrazide. The derivatization reaction proceeds in aqueous solution in the presence of pyridine and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide at 37 degrees C. The resulting derivatives were separated on a reversed-phase column (YMC Pack ODS-A) with isocratic elution and were fluorimetrically detected at 440 nm with excitation at 365 nm. The detection limit (signal-to-noise ratio=3) for valproic acid added to serum sample was 0.1 microg (700 fmol)/ml serum sample (2.3 fmol on column). The method was applied to determine the unbound- and total-valproic acid levels in the serum obtained from three healthy volunteers after oral administration of the drug (600 mg).
Hara
S
S
Faculty of Pharmaceutical Sciences, Fukuoka University, Japan.
Kamura
M
M
Inoue
K
K
Fukuzawa
M
M
Ono
N
N
Kuroda
T
T
D000328:Adult; D000927:Anticonvulsants / Q000097:blood; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D013050:Spectrometry, Fluorescence; D014635:Valproic Acid / Q000097:blood*
D000927:Anticonvulsants; D014635:Valproic Acid