Facile synthesis of ZIF-67C@RGO/NiNPs nanocomposite for electrochemical non-enzymatic sensing platform of nitrite

A novel non-enzymatic   electrochemical sensing platform for nitrite, composed of Co-based porous metal organic frameworks (ZIF-67), reduced graphene oxide (RGO), and nickel nanoparticles (NiNPs), was developed. The prepared ZIF-67, RGO and ZIF-67C@RGO were characterized using scanning electron microscopy (SEM) and powder X-ray diffraction (XRD). The fabricated nitrite sensor, ZIF-67C@RGO/NiNPs/GCE, exhibits a higher catalytic current intensity than that of NiNPs/GCE, ZIF-67C/GCE, ZIF-67C/NiNPs/GCE, and ZIF-67C@RGO/GCE. The catalytic current change of the amperometric i - t curve of nitrite demonstrated a linear relationship with the concentration in the linear range of 0.2–123 μM (R 2  = 0.9936) and 123–473 μM (R 2  = 0.998), and the limit of detection (LOD) reached 0.086 μM. Furthermore, the ZIF-67C@RGO/NiNPs/GCE showed good stability, reproducibility, and anti-interference ability. This developed sensor was successfully applied to the detection of nitrite in ham sausage.