Kinetics of heroin deacetylation in aqueous alkaline solution and in human serum and whole blood.

A kinetic study of heroin hydrolysis in alkaline aqueous solution at room temperature was conducted by a gas chromatographic method to measure the consecutive reactions of diacetylmorphine to monoacetylmorphine and of monoacetylmorphine to morphine. A first-order reaction was observed in both instances, and the rate for the deacetylation of heroin was greater than that of monoacetylmorphine. The rates of in vitro hydrolysis of diacetylmorphine in human whole blood and in serum were compared by the same method. Diacetylmorphine was hydrolyzed twice as rapidly in blood as in serum. While morphine was an end product of hydrolysis in the blood, it was absent in the serum.