DETERMINATION OF MERCURY(II), METHYLMERCURY AND ETHYLMERCURY IN THE NG ML RANGE WITH AN ELECTROCHEMICAL ENZYME GLUCOSE PROBE/

Hg(II), methylmercury and ethylmercury have been determined with an el ectrochemical glucose probe. Mercury and its compounds inhibit the enz yme invertase which, in presence of its substrate, sucrose, produces g lucose. When invertase is in presence of mercury its activity decrease s; this causes a decrease of glucose production, which is monitored by the glucose sensor and correlated to the concentration of mercury in solution. Parameters such as pH, enzyme concentration, substrate conce ntration, and reaction and incubation time were optimized. Results sho wed that mercury, methylmercury and ethylmercury can be detected direc tly in aqueous solution in the range 2-10 ng/ml.