Efficient direct electrocatalysis of nano-dodecahedron for the highly sensitive and selective detection of rutin

Herein, hollow and porous nano-dodecahedron embedded with cobalt oxide nanoparticles (HPND-CN) was prepared for the detection of rutin (Rut). HPND-CN was synthesized by the pyrolysis of zeolitic imidazolate frameworks (ZIFs). HPND-CN displayed a uniform rhombic dodecahedral morphology. For the main architecture, the original framework was carbonized after pyrolysis leading to a porous graphitized polyhedron with nitrogen doping. Notably, in the polyhedron, spherical cobalt oxide nanoparticles with more CoO and less Co 2 O 3 were evenly implanted. With embedded oxide nanoparticles, active doping species, polyhedral morphology, and porous graphitized structure, HPND-CN displayed a strong electrocatalysis towards the redox of Rut. A pair of well-defined symmetric peaks for Rut redox was clearly observed. Based on the electrocatalysis of HPND-CN, an efficient Rut sensor was developed with a low detection limit of 1.9 nM and broad detection range from 7.0 nM to 1.0 μM. HPND-CN prepared sensor also exhibited a superb selectivity showing no interference from common inorganic ions, carbohydrates, and amino acids. Besides, excellent repeatability, reproducibility and reliability were observed. Moreover, HPND-CN sensor was successfully applied to the measurement of Rut in health-care tablets with convinced results, indicating a substantial electrochemical sensing platform for the electrocatalysis and detection of macromolecules.