Fabrication of a solid-state ion selective electrode based on polypyrrole conducting polymer for As (V) ion

A pencil graphite electrode (PGE) electrodeposited by polypyrrole conducting polymer doped with arsenate ion (PGE/PPy/As) was prepared and used as potentiometric sensor electrode for determination of As(V). Electropolymerisation reaction for preparing of As(V) sensor electrode was carried via applying a constant potential of 0.90V on PGA as working electrode versus saturated calomel electrode (SCE) in a solution containing 0.40M pyrrole and 0.030M Na2HAsO4 as electrolyte. The constructed electrode displayed a linear and near Nernstian response (28.25 +/- 0.30mV/decade) to As(V) ions in the concentration range of 5.0x10(-5) to 1.0x10(-1)M. A detection limit of 2.8x10(-5)M and a fast response time (<= 10s) was observed during measurements. The working pH range of the electrode was 6.5-10.0 and lifetime of the sensor was at least 60 days.