Analysis of some antispasmodic drugs: oxyphencyclimine and glycopyrronium bromide

Oxyphencyclimine hydrochloride (via its tertiary amine group) and glycopyrronium bromide (via its quaternary ammonium group) were analysed by two different colorimetric methods. The first method depends on the dye-salt formation method using tropeolin ooo as the anionic dye and 1,2-dichloroethane as solvent for the extraction of the formed ion pairs. The coloured ion pairs have maximum absorption at 483-486 nm. The second method is based on the use of citric acid-acetic anhydride reagent. The coloured complex has maximum absorption at 562-565 nm.