Fabrication of Co₃O₄ particles-modified multi-walled carbon nanotube and poly(phenosafranine) composite electrode for selective and sensitive rutin detection

The preparation and characterisation of a new composite electrode with Co3O4 particles-modified multi-walled carbon nanotube (MWCNT) and poly(phenosafranine), as well as its novel application for the voltammetric detection of rutin was described. The resulting composite electrode was characterised using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS). In the optimised experimental conditions, the oxidation peak current (I-pa) of rutin showed a linear increase in concentration, between 0.008-0.6 and 0.80-6.0 & mu;mol L-1, with a detection limit of 0.00379 & mu;mol L-1. Due to its good selectivity and stability, the composite electrode was successfully applied in detecting rutin in pharmaceutical formulations.