Iridium oxide and palladium modified nitric oxide microsensor

An electrochemical microsensor, constructed by chemical modification of Naf ion, poly(vinyl pyridine) (PVP), palladium and iridium oxide onto a platinu m microelectrode, has been developed for the determination of nitric oxide (NO). This microsensor exhibits excellent catalytic activity toward NO oxid ation, which is confirmed by differential pulse voltammetry. Cyclic voltamm etry and differential pulse amperometry are also performed to measure NO. T he catalytic peak current is found to be linear with the NO concentration i n the range 5.8x10(-8)-6.4x10(-6) mol/l, with a correlation coefficient of 0.9985. The detection limit of the microsensor is 1.5x10(-8) mol/l. In addi tion, the microsensor is also very selective with respect to interferents s uch as ascorbic acid, dopamine, and nitrite. (C) 1999 Elsevier Science B.V. All rights reserved.