Ultrasensitive and Selective Electrochemical Detection of Sudan I Based on Platinum Nanoparticles Functionalized Cobalt Trioxide and Carbon Nanotubes Derived Zeolitic Imidazolate Frameworks

Ultrasensitive determination of Sudan I is critically important for food products due to its potential carcinogenicity. Herein, an electrochemical sensor was developed for Sudan I detection by using nanocomposites-based glassy carbon electrodes (GCE). Cobalt trioxides (Co3O4) dodecahedron were initially derived from zeolitic imidazolate frameworks (ZIF) and interconnected by carbon nanotubes (CNTs). After that, the Co3O4-CNTs complexes were functionalized with platinum nanoparticles (PtNPs), giving rise to a hierarchic system (PtNPs@Co3O4-CNTs/GCE) ultrasensitive to the cooperative binding activity of Sudan I. The electrochemical responses of as-proposed PtNPs@Co3O4-CNTs/GCE sensors have been evaluated toward Sudan I detection under different optimum conditions. Especially, the obtained results demonstrated that the Pt4.5NPs@(Co3O4)1- (CNTs)1/GCE sensor exhibits the superior electrochemical responses with high sensitivity (27870 mu A.mM(- 1).cm(-2)), wide linear range (0.03 mu M-100 mu M) and low limit of detection (0.005 mu M, S/N = 3). These results are promising for the development of high performance sensors of Sudan I which can be used for various food applications.