Thin-layer chromatographic method for separation and determination of papaverine and its oxidation products

A method is presented for the separation of papaverine, papaverinol and papaveraldine by TLC on silica gel with chloroform saturated with ammonia as the solvent system. The spots are extracted with absolute methanol and each compound determined spectrophotometrically in 1 M hydrochloric acid. Papaveraldine is also determined polarographically in Britton-Robinson buffer, pH 4.1, after its separation and elution. The method is rapid and sensitive and permits the determination of papaverine, after its extraction from drugs, without interference by papaverinol and papaveraldine.