A novel platform based on MnO2 nanoparticles and carboxylated multi-walled carbon nanotubes composite for accurate and rapid determination of curcumin in commercial food products

In this paper, a sensitive electrochemical sensor based on MnO2 nanoparticles functionalized carboxylated multi -walled carbon nanotubes (MnO2-c-MWCNTs) was prepared for the determination of curcumin. The synthesized materials have been fully characterized by instruments, such as X-ray diffraction (XRD), scanning electron mi-croscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The electro-chemical behavior of curcumin on the MnO2-c-MWCNTs modified glassy carbon electrode (MnO2-c-MWCNTs/ GCE) was investigated in detail by CV and chronocoulometry (CC). The electrochemical reaction mechanism of curcumin on the modified electrode was also discussed. In 0.1 M H2SO4 solution, the peak current showed a good linear dependence on curcumin concentration in the range of 0.01-1 mu M and 1-80 mu M, The method has high sensitivity (3.30 mu A mu M-1 cm( -1)), and the detection limit is 6.0 nM. At the same time, the MnO2-c-MWCNTs/GCE has good anti-interference ability and stability. In addition, the sensor was used for the accurate and rapid determination of curcumin in commercial food samples, which shows its good potential for practical application.