FIELD: experimental and clinical medicine, biology. SUBSTANCE: plasma is obtained, reaction mixture with oxidation substrate as paraphenylenediamine is prepared. Plasma is incubated at equal volumes in two parallel samples in reaction mixtures, one of which contains buffer, paraphenylenediamine and hydrogen peroxide, the other has analogous ingredients with sodium azide. Samples are then thermostated under standard conditions together with control samples which are identical according to composition to the first and the second experimental samples, but with no blood plasma. Then optical density is determined. The ratio of optical density differences for the first control sample and the first experimental sample by taking into account a correction to optical density of the first control sample characterizes total antioxidant blood plasma activity. The ratio of optical density differences for the second control sample and the second experimental sample to optical density of the second control sample characterizes nonfermentative-conditioned antioxidant activity. The difference between total antioxidant activity and nonfermentative-conditioned activity characterizes fermentative-conditioned antioxidant activity of blood plasma. EFFECT: higher efficiency to reduce terms of treatment, simplify technique and increase its informativity. 2 tbl
