Novel three‐dimensional senor based on nanodendrites for nitrite determination

Abstract

As a common pollutant in food, nitrite has carcinogenicity after long-term consumption. Rapid detection of nitrite in food is an urgent problem to be solved. In the study, poly dimethyl diallyl ammonium chloride-reduced graphene oxide (PDDA-RGO) was prepared by chemical reduction method, and then three-dimensional copper nanodendrites (Cu NDs) were successfully electrodeposited on the surface of PDDA-RGO modified glassy carbon electrode (GCE). The sensor has been successfully applied to the detection of nitrite. PDDA as a hydrophilic cationic polymer effectively avoided the aggregation of RGO. The RGO in the composite material provided a framework for the growing of Cu NDs, which efficiently promoted electron transfer. Moreover, the Cu NDs exhibited pivotal performance in improving the sensitivity and enlarging the specific surface area. The prepared sensing nanocomposites were characterized by cyclic voltammetry (CV), transmission electron microscopy (TEM), scanning electron microscope (SEM), and energy dispersive spectrometer (EDS). Under the optimal conditions, the limit of detection (LOD) of the fabricated sensor was 0.06 μM (S/N = 3), the highest sensitivity was 0.763 μA·μM−1·cm−2, and with linear range of 1–15,000 μM. The sensor performed well in terms of stability and anti-interference, and it provided a new and feasible method for the detection of nitrite in food.