A versatile electrochemical, colorimetric, and visible light excitable turn-on fluorescent probe for stress-induced H₂S detection

Hydrogen sulfide (H₂S) holds a distinct role in cell biology. Its level is intricately linked to the homeostasis of the biological environment, underscoring the significance of developing techniques capable of detecting H₂S in biological systems. A single probe that offers versatility across different detection techniques opens opportunities for advancements in sensing H₂S in various fields. A nitronaphthalimide derivative, NMO prepared using a simple synthetic protocol, has been studied as an electrochemical, colorimetric, and turn-on fluorescence probe for H₂S. NMO displayed a detection limit of 9.95 mM and 4.36 mM in the UV–visible and colorimetric studies, respectively, whereas the fluorometric and square wave techniques confirmed lower detection limits of 98.4 μM and 1.24 mM, correspondingly. Further, the real-time imaging of HEK293T cells using NMO during stress-induced autophagy is demonstrated.