A sensitive and fast electrochemical sensor based on copper nanostructures for nitrate determination in foodstuffs and mineral waters

Abstract

A fast, sensitive and accurate electrochemical sensor based on copper nanostructures for electrocatalytic determination of nitrate has been developed. Cyclic voltammetry and hydrodynamic amperometry were employed to characterize the response of the sensor to nitrate that changes linearly in the concentration range from 1 to 35 μM. The repeatability of measurements for nitrate was evaluated as 2.3% (N = 15) and the limit of detection of the method was found to be 0.59 μM (S/N = 3). The content of nitrate in foodstuffs and mineral water samples was determined by the proposed and the reference method based on Griess protocol at the 95% confidence level. No interferences were observed from nitrite ions on the nitrate analysis. The interference from chloride ions was also examined.