Preparation of Au/Pt/Ti3C2Cl2 nanoflakes with self-reducing method for colorimetric detection of glutathione and intracellular sensing of hydrogen peroxide

A novel two-dimensional nanolayered Ti3C2Cl2 MXene material derived from MAX phase was synthesized through a HF-free method based on elemental replacement reaction in the A atom of traditional Ti3AlC2 MAX phase and ZnCl2 molten salts, which possess large specific surface areas, excellent electric conductivity and reducing property. Then the Au/Pt bimetallic nanoparticles decorated Ti3C2Cl2 nanoflakes were synthesized by a self-reduction method with Ti3C2Cl2 as a natural reducing agent and supporter, which possess peroxidase mimic activity and oxidase mimic activity, simultaneously. Based on the prominent catalytic activity of Au/Pt/Ti3C2Cl2 nanocomposite, a novel colorimetric platform was developed for in situ sensing of hydrogen peroxide (H2O2) released from live HeLa cells and colorimetric detection of glutathione (GSH), with the detection ranges of 50–10000 μM and 0.1–20 μM, the detection limits were 10.24 μM and 0.07 μM, respectively. These results allow utilization of the easily accessible 2D surface for the design and application of 2D layered material-supported MXene nanocomposites catalysts in intracellular biosensing.