Visual and quantitative determination of dopamine based on CoxFe3−xO4 magnetic nanoparticles as peroxidase mimetics

CoxFe3−xO4 was proved to possess higher peroxidase-like activity comparing with Fe3O4 MNPs. It could effectively catalyze the reaction between 3,3,5,5-tetramethylbenzidine (TMB) and H2O2 under 40 °C within 15 min. So this proposed method was used for measuring dopamine. The color variation was very obvious on visual observation, which offered a convenient approach to detect DA by naked eye.