Application of bromopyrogallol red for the extractive-spectrophotometric determination of chlorpromazine

Bromopyrogallol red has been tested as an analytical reagent for the determination of chlorpromazine. It reacts in acid medium with chlorpromazine hydrochloride forming a coloured complex of the ion-pair type, which can be quantitatively extracted into benzene. This property has been successfully used for the extractive-spectrophotometric determination of chlorpromazine. Beer's law was obeyed in the range 5-50 ppm of chlorpromazine hydrochloride. The relative standard deviation was 0.8% (n = 10).