Spectrophotometric determination of sodium dodecylbenzenesulfonate using triphenylmethane dyes

Abstract

Spectrophotometric determination of sodium dodecylbenzene-sulfonate (DBS) has been investigated by use of triphenylmethane type dyes such as Methyl Violet, Malachite Green and Brilliant Green.
DBS reacted with these reagents in glycine buffer solution and its benzene extract gave green coloration.
The effects of pH, concentrations of glycine buffer solution and the reagents, and temperature on the extraction and stability of the color as well as the effects of various solvents and coexisting salts have been investigated.
The result indicated that the absorption and concentration of DBS followed the Beer's law at the maximum absorption of 600 mμ in Methyl Violet, at 635 mμ in Malachite Green and at 645 mμ in Brilliant Green at the concentration of 30 μg/15 ml benzene.
The spectrophotometric determination of a trace amount of DBS by use of Brilliant Green was rapid and sensitive.