Plasma 3,4-dihydroxyphenylacetic acid

Eldrup E, Clausen N, Scherling B, Schmiegelow R. Evaluation of plasma 3,4-dihydroxyphenylacetic acid (DOPAC) and plasma 3,4-dihydroxyphenyialanine (DOPA) as tumor markers in children with neuroblastoma. Scand J Clin Lab Invest 2001 61 479-90. 

Holmes C, Eisenhofer G, Goldstein DS. Improved assay for plasma dihydroxyphenylacetic acid and other catechols using high-performance liquid chromatography with electrochemical detection. J Chromatogr B Biomed Appl 1994 653 131-8. 

Yeung PK, Buckley SJ, Pedder SC, Dingemanse J. Determination of 3,4-dihydroxyphenylacetic acid and 5-hydroxyindoleacetic acid in human plasma by a simple and rapid high-performance liquid chromatography assay. J Pharm Sci 1996 85 451-3. 

C.R. Benedict, Simultaneous measurement of urinary and plasma norepinephrine, epinephrine, dopamine, dihydroxyphenylalanine, and dihydroxyphenylacetic acid by coupled-column high-performance liquid chromatography on Cg and C g stationary phases, J. Chromatogr, 385, 369-375 (1987). 

An optimization procedure for the separation of epinephrine bitartrate, L-DOPA, 3,4-dihydroxyphenylacetic acid, notepinephrine-HCl and dopamine-HCl (with 3,4-dihydroxybenzylamine-HCl as internal standard), was described by He et al. [1075]. A C,8 column was used in conjunction with an electrochemical detector (-1-0.6 V vs, Ag/AgCl). A window diagram of relative retention times for adjacent eluting solute pairs (i.e., lR2/tRi) resulted in three acceptable solvent composition windows. The optimal solvent conditions were found to be 2.5/97.5 acetonitrile/water (0.23% sodium acetate with 0.02% EDTA and 0.066% sodium heptanesulfonate adjusted to pH 3.9 with monochloroacetic acid). Elution was complete in <30 min and all peaks were well resolved. Detection limits for dog or human plasma samples were reported as 10pg/mL for epinephrine and norepinephrine. 

Fig. 2.3. Diagnostic flow-chart in the differentiation of defects of biogenic amine neurotransmitter metabolism. The correct differential diagnosis depends on the pattern of amines and their metabolites in either urine, CSF or plasma. represents increased values, [ represents lowered values. 5HIAA 5-hydroxyindoleacetic acid HVA homovanillic acid 5HT serotonin 30MD 3-0-methyldopa DOPAC dihydroxyphenylacetic acid 3MT 3-methoxytyramine NMN norme-tanephrine VMA vanillylmandelic acid DOPS dihydroxyphenylserine MHPG 3-methoxy-4-hydroxyphenylglycol Y yes N no. Plasma and CSF levels have not been analysed but they probably reflect those seen in urine. For interpretation of quantitative results see pathological values.

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