Single-layer MnO2 nanosheets for sensitive and selective detection of glutathione by a colorimetric method

Abstract The rapid, sensitive and selective detection of glutathione (GSH) is of great importance in the biological systems. In this work, a template-free and one-step method was used to synthesize the single-layer MnO 2 nanosheets via a redox reaction. The resulting product was characterized by XRD, TEM, FTIR, XPS and UV–vis absorption. The addition of GSH results in the change of solution color depth owing to the occurrence of a redox reaction between MnO 2 and GSH, enabling colorimetric detection of GSH. At a pH of 3.6, the proposed sensor gives a linear calibration over a GSH concentration range of 10–100 μM, with a rapid response of less than 2 min and a low detection limit of 0.5 μM. The relative standard deviation for seven repeated determinations of GSH is lower than 5.6%. Furthermore, the chemical response of the synthesized MnO 2 nanosheets toward GSH is selective. Owing to the advantages with good water solubility, rapid response, high sensitivity, good biocompatibility and operation simplicity, this two-dimensional MnO 2 -based sensing material might be potential for detecting GSH in biological applications.