A fluorescent probe for turn‐on sensing of glutathione using red emitting gold nanoclusters

Glutathione (GSH), an oxidative stress biomarker plays a major role in different pathological processes and lead to a vast number of diseases including cancer. Biologically, cystine uptake is a fundamental factor in maintaining GSH levels in cells; however, the interaction between cystine and GSH in biological systems is least explored in developing sensors for GSH. In the present work, we have explored this interaction as the fundamental factor in “turn‐on” sensing of GSH from body fluids using a fluorescent gold nanocluster platform. The experimental results revealed that the probe displayed appreciable performance for GSH over a linear range from 0.2 mM to 1.3 mM with a limit of detection (LoD) of 0.43 μM. The probe also revealed sensitive as well as selective response towards GSH even in the presence of possible co‐existing interferants and provided satisfactory recovery percentage of 94.17 % to 108.12 % from real serum samples. These findings of the present study can be extended in future applications of sensing GSH from clinical samples.