[Amperometric sensor for recording the results of immunoenzyme analysis]

A technique for quantitative determining horseradish peroxidase was developed using an amperometric sensor that makes it possible to register up to 50 pM of the enzyme in the reaction of the peroxidase oxidation of iodide ions by hydrogen peroxide. The sensor, composed of combined carbon and Ag/AgCl electrodes, is intended for enzyme immunoassay and may be used for registering the results in the very wells of the polystyrene plates widely used in clinics and laboratories. The dependences of the initial rate of the enzymatic reaction on the substrate concentration and pH of the medium were determined, on the basis of which the conditions for the optimal operation of the sensor were found. The amperometric and spectrophotometric methods of registration on a model system for determining antibodies against X-virus of potato were compared in order to show a possibility of the sensor applying to enzyme immunoassay.