Radiochromatographic Method for –SH Determination in Proteins by [203Hg] p-Hydroxymercuribenzoate

Abstract

A radiochromatographic method which allows the evaluation of the number of sulfhydryl and disulfide groups per molecule of protein, in native or denatured (reduced or not) form, in terms of –SH groups, is proposed. The experiments were performed by using ²⁰³Hg-labelled p-hydroxymercuribenzoate as reagent and known concentrations of bovine serum albumin (BSA) were used as a standard. The method is precise with a mean RSD of 3.0, 6.5 and 2.5% for native, denatured and reduced BSA, respectively; the accuracy is in the range 1.9–5.0%.