A new amperomctric sensor for nanomolar detection of iodate was fabricated based on the glassy carbon electrode modified by electrodeposited iridium oxide (lrOx ) film. l’hc characterization of iridium oxide films and its electrochemical properties were investigated by atomic force microscopy (AFM), scanning electron microscopy (SliM) and cyclic voltammetry. The modihed elect rode shown well defined and reversible redox couple at wide pH range(l- 13). Due to the importance role of iodine and its derivatives (lO, 104) in biological process, their determination are very important. In the present study for the first time this modified electrode was used in electrocatalytic reduction of iodaie in acidic solution. GC-1r2O modified electrode was shown excellent electrocatalytic activity toward iodate at unusual positive potential. The modified electrode was used successfully for nanomolar detection of iodate , using hydrodynamic amperometry technique. The ability of the sensor for iodate detection was evaluated by measuring iodate in iodized salt sample. This sensor has some distinct advantattes over other sensor, such as unusual positive potential reduction of iodate , simple preparation process, inherent and long-term stability, excellent catalytic activity over a wide pH range, and simplicity of preparation.
