A chromatographic method of analysis for thiols

Abstract
A method is described for the paper chromatography of thiols. The thiol is first treated with N-(-4-hydroxy-l- naphthyl) isomaleimide and after chromatographic development detected with tetraazotized di-o-anisidine. The technique is applicable to a variety of thiols, but is not yet suitable for alkyl thiols. Quantities of thiols as low as 0.3 um-mole were detected, and under optimum conditions 0.1 um-mole was visualized under UV light. The sensitivity of the method is therefore superior to the N-ethylmaleimide detection of thiols or the ninhydrin detection of 2-amino acids. A sample application of the method is presented.