DETERMINATION OF THE STABILITY OF DOPAMINE IN AQUEOUS-SOLUTIONS BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

Methods for the ananlysis of dopamine and its degradation products in aqueous solutions is described. The technique of reverse phase chromatography with electrochemical detection is used to investigate the stability of dopamine in various aqueous solutions. In neutral and basic solutions, dopamine is rapidly oxidized by dissolved oxygen to form degradation products. The results demonstrate that dopamine is stable in 0.1 N HCl solution, pH < 1. The study indicates that EDTA can slow down the oxidation process. The detection limit for the analysis of dopamine is 0.1 mu M with 100 mu l injection.