A novel colorimetric determination of reduced glutathione in A549 cells based on Fe3O4 magnetic nanoparticles as peroxidase mimetics

In this paper, a novel and simple colorimetric method for the determination of reduced glutathione (GSH) based on Fe3O4 magnetic nanoparticles (MNPs) as peroxidase mimetics was developed. The Fe3O4 MNPs prepared via a coprecipitation method, which possess intrinsic peroxidase-like activity, were used as a catalyst in the color development reaction of a peroxidase substrate 2,2'-azino-bis(3-thylbenzo-thiazoline-6-sulfonic acid) diammonium salt (ABTS) and H2O2. The existence of GSH can consume H2O2 and cause a color change of the reaction system which can be detected by the naked eye. Accordingly, the GSH can be detected by measuring the wastage of H2O2. A good linear relationship was obtained from 3.0 to 30.0 mu M for GSH. Good recoveries ranging from 96.7 to 107% were obtained. Furthermore, it was used to detect GSH in A549 cells.