Comparative Study of Fluorometric and Electrochemical Detection of Catecholamine,Serotonin, and Metabolites in Rat Brain by High-Performance Liquid Chromatography

Abstract

A high-performance liquid chromatograph connected to a newly designed fluorometer was used for the simultaneous determination of norepinephrine, dopamine, serotonin, 3-methoxy-4-hydroxyphenylglycol (MHPG), homovanillic acid, and 5-hydroxyindoleacetic acid by measuring native fluorescence. These amines and metabolites extracted from the frontal cortex of a rat were purified by adsorption on alumina and an extraction with ethyl acetate and separated in the chromatograph with an ODS column. The detection limits ranged from 0.5 to 3 pmoles. Compared to the electrochemical (EC) detection at an electrode potential of 0.8 V, the sensitivity was almost the same or somewhat lower, but MHPG was highly fluorescent. In the fluorometry, large front peaks observed in the EC detection did not appear, and interfering peaks were not observed.