FIELD: medicine. SUBSTANCE: invention relates to the field of physicochemical analysis methods, in particular - to the analysis of solutions regarding the quantification of the antioxidant capacity. The invention can be used for the analysis of food items and pharmaceutical items and consists in a potentiometric method for determining the antioxidant capacity using 2,2'-diphenyl-1-picrylhydrazyl, characterized by the fact that the initial solution of 2,2'-diphenyl-1-picrylhydrazyl is premixed with a concentration of CDPPH in a solvent and the analysed solution, into which, after mixing, an electrolyte is added and the potential E1 is measured, the first additive 2,2'-diphenyl-1-picrylhydrazyl is introduced at the concentration of C'DPPH and the potential E2 is measured, the second additive is introduced 2,2'-diphenyl-1-picrylhydrazyl at the concentration of C''DPPH and the potential E3 is measured, the antioxidant capacity of the analysed solution AOEDPPH is determined by solving simultaneous equations. By varying the concentrations of the original DPPH and making successive additions, a significant expansion of the determined concentration ranges and a decrease in the determination error are achieved. EFFECT: technical result of the invention is a developed potentiometric method, which allows to analyse items with own colour of any intensity. 3 cl, 5 dwg, 3 ex.
