A BIOSENSOR AS WARNING DEVICE FOR THE DETECTION OF CYANIDE, CHLOROPHENOLS, ATRAZINE AND CARBAMATE PESTICIDES

The determination of cyanide, chlorophenols, atrazine, dithiocarbamate and carbamate pesticides is described, utilizing an amperometric bios ensor constructed by the electropolymerization of a pyrrole amphiphili c monomer-tyrosinase coating. Measurements were carried out with catec hol, dopamine, L-DOPA or epinephrine as an enzyme substrate; the enzym atically generated quinoid products being electroreduced at -200 mV vs . SCE. The detection of these water pollutants was performed via their inhibiting action on the tyrosinase electrode. The characterization o f the inhibition processes (competitive/non-competitive) and their rev ersibility were examined. The detection limits are 0.4, 2, 2, 4 and 0. 02 mu M for 3,4-dichlorophenol, chloroisopropylphenylcarbamate, 3-chlo roaniline, atrazine and cyanide, respectively.