Observations on the use of titan yellow for the determination of magnesium with special reference to soil extracts

Abstract

Examination by paper and thin-layer chromatography of several preparations of titan yellow from different manufacturers has shown them to be complex mixtures.

By using a titan yellow selected chromatographically, it has been possible to improve the stability and sensitivity of the coloured complex produced with magnesium. Studies have been made of the effects of alkalis, interfering ions and protective colloids, and the use of gelatin with a lithium hydroxide-glycine buffer is proposed for the determination of magnesium in soil extracts. Results have been compared with those obtained by atomic-absorption spectroscopy and show close correlation.