[Quantitative determination of tissue disulfide groups by reverse amperometric titration]

A method of reversed amperometric titration for estimation of content of S- S-groups in biological materials is described. The method is based on splitting of disulphide groups in reaction with a reducing agent (Na2SO3) in presence of an excess of metal ions (Ag+, Hg2+), which form a mercaptide bond (AgS) with SH-groups. The excess of free metal ions was titrated with the equimolar solution of thiol (unithiol, cysteine). The method is comparatively simple and enables to estimate S- S groups in presence of air oxygen and enzymatic systems.