Determination of Dithiodiglycolic Acid in Cold Wave Lotions by High Performance Thin Layer Chromatography

A simple and rapid method by high performance thin layer chromatography (HPTLC) was studied for the determination of dithiodiglycolic acid (DTDGA) in hair-waving solutions. Sample and standard solutions were spotted on a silica gel plate. Immediately the plate was developed with diisopropylether-formic acid-water (90 : 7 : 3 v/v) for the separation of DTDGA and thioglycolic acid (TGA). The plate was sprayed with detecting solution : dissolve CuSO4·5H2O in a little distilled water, made up with methanol. DTDGA and TGA was visualized by heating for 30 min at 100°C. Densitometric determination was carried out with TLC scanner. DTDGA in the range of 0.5-20.0 μg was determined by the proposed method with spotting 1 μl of samples. And the HPTLC procedure in this paper was applicable to the quantitative analysis of DTDGA without an influence of other ingredients in hair-waving solutions.