An Au-Pd@MWCNT/graphene Modified Carbon Paste Electrode as a Novel Nano-Composite Sensor for the Trace Determination of Nitrite

This paper has presented a novel strategy to carry out the direct and sensitive determination of nitrite ion in different and complex matrices based on a new nano-composite carbon paste electrode composed of (Au-Pd@MWCNT/Gr)-CPE. The characteristics of the proposed nano-materials were investigated by scanning electron microscopy and X-ray diffraction. The effects of various experimental parameters on the electrochemical response of the nitrite ions were assayed and optimized. Under the optimized conditions, the calibration curve for nitrite ion concentration was linear in the range of 0.02-55.0 μmol L-1 with the detection limit of 9.44 nmol L-1. In addition, the suggested sensor was successfully applied to the determination of nitrite ion in sausages, cheese, plant foodstuffs, soil, mineral water and tap water samples with satisfactory results. However, the prepared sensor may hold great promise for fast, simple and sensitive detection of nitrite in various real samples