A novel application of iron oxide nanoparticles for detection of hydrogen peroxide in acid rain

Abstract

Determining the concentration of hydrogen peroxide (H 2O 2) is of great importance in food, pharmaceutical, environmental and clinical analyses. Horseradish peroxidase (HRP), an enzyme specifically catalyzing the oxidative reaction of H 2O 2 to develop color reaction, has been widely used for measuring H 2O 2 concentration. However, owing to the instability and high cost of this enzyme, discovering efficient mimics of peroxidase has been important to conquer these disadvantages of protein catalyst. Recently we have found that Fe 3O 4 magnetic nanoparticles (Fe 3O 4 MNPs) possess intrinsic peroxidase-like activity, which can catalyze oxidation of various peroxidase substrates in the presence of H 2O 2. Based on this finding, we developed a spectrometric method using Fe 3O 4 MNPs as a catalyst to determine H 2O 2 in rainwater. Our data show that the Fe 3O 4 MNPs are efficient catalysts to determine H 2O 2 in rainwater. Compared to HRP, the Fe 3O 4 MNPs are reusable and economical and these characteristics make the particles a board range of applications in determining H 2O 2 in the rainwater.