DETERMINATION OF ORGANOMERCURY COMPOUNDS USING IMMOBILIZED PEROXIDASE

The effect of organomercury compounds (methyl-, ethyl- and phenylmercu ry) on the activity of immobilized peroxidase was studied. Peroxidase was immobilized in chitosan films in wells on a polystyrene plate and on chromatography paper. The oxidation reactions of o-dianisidine, o-p henylenediamine and 3,3',5,5'-tetramethylbenzidine by H2O2 were used a s indicators. The rate of all the indicator reactions was monitored vi sually by measuring the time of appearance of the colour of the oxidat ion product, The liberating effect of organomercury compounds on perox idase immobilized on both the above mentioned supports using o-dianisi dine oxidation in the presence of the inhibitor phenylthiourea and the effect of organomercury compounds on the duration of an induction per iod of 3,3',5,5'-tetramethylbenzidine oxidation in the presence of die thyldithiocarbamate catalysed by paper-immobilized peroxidase were use d for the development of enzymatic test procedures for the determinati on of organomercury compounds at concentrations of 0.02-1000 mu M. The relative standard deviation (n=3) at the lower limits of their analyt ical concentration ranges in the proposed test procedures using o-dian isidine are 18-23% (n=3).