Inhibition of Epinephrine Oxidation in Weak Alkaline Solutions

Abstract

The effect of sodium metabisulfite and cysteine on the oxidation of epinephrine in weak alkaline solutions was studied. The fluorescent intensity of the reacting mixture also was measured. Sodium metabisulfite in 2×10−3M NaOH at concentrations lower than 3×10−5M had no effect on epinephrine oxidation; however, in concentrations from 5×10−5 to 3×10−4M, it greatly accelerated this process. Its inhibitory action appeared only in concentrations greater than 5×10−4M, The mechanism of these reactions also was explained. Cysteine in 2×10−3M NaOH inhibited the oxidation of epinephrine even in concentrations of 7×10−5M.