Ammonia → Benzoic Acid

Participants

Reaction Steps

Plasma samples were aliquoted and non-radioactive cocaine, benzoyl ecgonine, and norcocaine were added in order to assist in the UV visualization of the compounds. Samples were then applied to silica TLC plates which were developed in two solvent systems: methanol, chloroform, and triethylamine (3:1:0.1); and ethyl acetate, methanol, water, and concentrated ammonia (85:10:3:1). Metabolites were identified by reference to control compounds run on the same plates. The bands were scraped off the plates and 3H-containing compounds were detected through scintillation counting. From the counts obtained the amount of cocaine, benzoyl ecgonine, benzoic acid, and norcocaine as percent of total counts was determined. The total radioactivity in the plasma was determined by scintillation counting of whole plasma. Benzoic acid is detected as a metabolite when cocaine degrades into ecgonine methyl ester and benzoic acid, and so is equimolar to the ecgonine methyl ester metabolite.

Provenance & Evidence