Highly sensitive and selective colorimetric detection of glutathione via enhanced Fenton-like reaction of magnetic metal organic framework

Glutathione (GSH) as a biothiol is an essential endogenous antioxidant related to various diseases. Since all the biothiols possess similar structures and reaction activities, it is still challenging to detect GSH over cysteine (Cys) and homocysteine (Hcy). In this contribution, we propose a novel approach to sensitively and selectively detect GSH based on Fe3O4/MIL-88-H2O2-methylene blue (MB) heterogeneous system via enhanced Fenton-like reaction. The magnetic metal organic framework (Fe3O4/MIL-88) exhibits synergistic effect on Fenton-like reaction by combining Fe3O4 with MIL-88. In this system, GSH can facilitate the degradation of MB in the presence of Fe3O4/MIL-88 and H2O2, so a detection method for GSH is established via a turn-off colorimetric process. Under the optimal conditions, this approach presents a good linear response to GSH concentration in the ranges of 0-0.55 μM and 0.55-3 μM, with a detection limit of 36.9 nM (3δ/S). Furthermore, the excellent sensitive and selective responses to GSH in serum sample make this assay a promising tool for biological applications due to its simplicity, high efficiency and low cost.