Determination of 5-oxides of pharmaceutically important phenothiazines by means of differential pulse polarography

Abstract

For the quantitative analysis of the sulphoxides (5-oxides) of pharmaceutically important phenothiazines in microgram amounts a method is developed using differential pulse polarography (DPP). It is suitable for the determination of at least 0.1 μol of the compounds. Surfactants present in the solution interfere. In degradation studies of phenothiazines isolation of the 5-oxides is necessary before the determination, since most phenothiazines show surface activity. The isolation is carried out by TLC. Standard deviation is about 4%.