N-methyl-2-pyrrolidone exfoliated graphene as highly sensitive analytical platform for carbendazim

Graphene nanosheets (GS) with approximately 10-15 layers was prepared via ultrasonic exfoliation of graphite powder in N-methyl-2-pyrrolidone (NMP), and confirmed using transmission electron microscopy (TEM) and atomic force microscopy (AFM). X-ray photoelectron spectra (XPS) and Raman spectra were employed to get further insights into the structural characteristics of exfoliated GS. On the surface of the GS modified glassy carbon electrode (GS/GCE), oxidation signals corresponding to carbendazim, a widely used pesticide, were greatly improved due to the higher accumulation ability, as determined by chronocoulometry. The oxidation mechanism of carbendazim was studied using a rotating disk electrode, and two electrons were transferred. Depending on the signal amplification of GS, a highly sensitive analytical platform for carbendazim was constructed. The linear range was from 1.0 to 300.0 mu g L-1 (0.005-1.57 mu M), and the detection limit was 0.15 mu g L-1 (0.78 nM). Finally, this newly developed sensor was used to detect carbendazim in ground water, soil, and cucumber samples with satisfactory accuracy.