Stability of 3,4-dihydroxyphenylacetic acid in plasma extracts assayed by high-performance liquid chromatography with electrochemical detection.
3,4-Dihydroxyphenylacetic acid (DOPAC) can be easily assayed by high-performance liquid chromatography (HPLC) with electrochemical detection at the same time as norepinephrine (NE), epinephrine (E), and dopamine (DA). The latter catecholamines are stable in perchloric acid extracts for over 6 h at 4 degrees C in the dark whereas DOPAC levels drop rapidly by more than 50% in 6 h at 4 degrees C in the dark. This study investigated the effects of reducing agents [ascorbic acid, dithiothreitol (DTT), reduced glutathione with or without a metal chelating agent (diethylenetriaminepentaacetic acid or ethylenediaminetetraacetic acid)] on DOPAC. Extracted with alumina using 0.65 mmol/1 DTT prior to HPLC and electrochemical detection, DOPAC remained stable in the perchloric acid extract for 2 h at 4 degrees C in the dark.
Candito
M
M
Laboratoire de Biochimie, Hôpital Pasteur, Nice, France.
Krstulovic
A M
AM
Chambon
P
P
D015102:3,4-Dihydroxyphenylacetic Acid / Q000097:blood* / Q000737:chemistry; D000328:Adult; D001205:Ascorbic Acid / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004229:Dithiothreitol / Q000737:chemistry; D004492:Edetic Acid / Q000737:chemistry; D004563:Electrochemistry; D005978:Glutathione / Q000737:chemistry; D006801:Humans; D008875:Middle Aged; D010084:Oxidation-Reduction; D004369:Pentetic Acid / Q000737:chemistry; D012016:Reference Values
D015102:3,4-Dihydroxyphenylacetic Acid; D004369:Pentetic Acid; D004492:Edetic Acid; D005978:Glutathione; D001205:Ascorbic Acid; D004229:Dithiothreitol