CAREER NETWORK World's one of the largest Research Career Network Benefits Academic & Industry jobs Project funding Visiting faculty positions Visiting scientist positions Invited talks and more... Register FREE Chemical Sensors 2011, 1: 5 Research Article Potentiometric application of solid contact nitrate selective electrode in leafy vegetables Muberra Andac*, Hilal Eren Department of Chemistry, Faculty of Science, Ondokuz Mayis University, 55139 Kurupelit-Samsun, Turkey Abstract A polyvinyl chloride (PVC) membrane NO3--selective electrode was constructed based on all-solid state technology. The potentiometric characterization of the electrode under steady-state conditions displayed a near-Nernstian response in the linear range from 1x10-1 to 1x10-6 mol L-1 with a sensitivity of 49.9 mV/decade of nitrate ion activity (aNO3-) and a detection limit of 5.5x10-7 mol L-1. The electrode had a very short response time (<3 s) and good reproducibility at a working pH range of 3-7. It can be used for four months without any considerable divergence in the slope of the concentration–potential curve. The constructed electrode was applied successfully in the determination of nitrate contents in commonly consumed leafy green vegetables. The obtained results show that, nitrate contents of fresh vegetables, obtained from bazaar in Samsun during the spring, were in the ranged of 198-2345 mg kg-1. Keywords Potentiometry; Nitrate; Polyvinyl chloride (PVC) membrane; All-solid state ion selective electrodes; Leafy vegetables