Novel enzymatic graphene oxide based biosensor for the detection of glutathione in biological body fluids

In this work, we report a novel enzymatic biosensor based on glutathione peroxidase (GSH-Px), graphene oxide (GO) and nafion for the electrochemical sensing of glutathione (GSH) in body fluids. GSH-Px was immobilized covalently via 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) onto modified glassy carbon electrode (GCE) decorated with GO and nafion and successfully used for sensing of GSH in the presence of H2O2 as catalyst with Michaelis-Menten constant about 0.131 mmol/L. The active surface are of GCE improve from 0.183 cm2 to 0.225 cm2 after modification with GO. The introduced biosensor (GSH-Px/ GO/nafion/GCE) was used for monitoring of GSH over the range 0.003-370.0 mu M, with a detection limit of 1.5 nM using differential pulse voltammetric (DPV) method. The GSH-Px/GO/nafion/GCE was successfully applied to the determination of GSH in real samples.

Automated summary

In this study, a novel enzymatic biosensor based on GSH-Px, GO, and nafion was developed for the electrochemical sensing of GSH in body fluids. The biosensor showed improved detection sensitivity and reliability, successfully used for the determination of GSH in real samples.