Use of gelatin in the differential-pulse polarographic determination and identification of synthetic colouring matters in drugs and cosmetics

Abstract

A systematic study has been made of the effect of gelatin on the polarographic behaviour of 16 food and three cosmetic synthetic colouring matters. Gelatin was shown to have a pronounced effect on the peak currents, and a lesser effect on the peak potentials, of some of the colouring matters, and these effects could be used to partially identify and determine these colouring matters. Applications to the analysis of a coloured gelatin capsule, a lipstick and a blusher are described.