Fluorometric Method for Quantitatively Estimating Urinary Dihydroxyphenylethylamine (Dopamine), Dihydroxyphenylalanine (Dopa), and Dihydroxyphenylacetic Acid (Dopac)

Abstract

Abstract A relatively simple, exact method is described for simultaneously estimating dopamine, dopa, and dopac in urine. The compounds are concentrated on alumina by an abbreviated batch technique and separated by "two solutions" paper electrophoresis at low voltage for 2 h. Fluorophores are developed by condensation with ethylenediamine. The fluorescent bands, eluted into water, are measured fluorometrically. This method was used to estimate the major free metabolites of dopa in urines from parkinsonian and hyperkinetic patients, and normal subjects. Compared with normal controls, dopamine excretion tended to be decreased in patients with parkinsonism, increased in hyperkinetic patients. The sum of the free metabolites (dopamine, dopac, and homovanillic acid) was significantly smaller for the patients with parkinsonism than for normal subjects.