Determination of sulfate after chromatography and toluidine blue complex formation

A rapid and simple method for the determination of sulfate involving a complex formation between inorganic sulfate and the dye, toluidine blue O, after chromatography, is presented. The method can be used for the determination of sulfate in the presence of interfering ions such as phosphate and citrate. Most of the ions have a different chromatographic migration in the solvent system employed. An added advantage is the measurement of the labile sulfate of mucopolysaccharides with accuracy.