Colorimetric assay of H_2O_2 using Fe_3O_4 nanoparticles as nanocatalyst

摘要

Fe_3O_4 nanoparticles were prepared, and catalyzed the reaction of H_2O_2-methyl orange. In pH 1.42 HCl-NaAc buffer solution, methyl orange has two absorption peaks at 331 nm and 506 nm. When Fe_3O_4 nanoparticles was added, it can catalyzed H_2O_2 oxidizing methyl orange to result in the absorption value decreased at 506 nm. The decreased absorption value is linear with the concentration of H_2O_2 in the range of 3.5-33 μmol/L. Based on this, a new colorimetric assay has been proposed for the determination of H_2O_2 in the water sample, with satisfactory results.