Intracellular detection of hazardous Cd²⁺ through a fluorescence imaging technique by using a nontoxic coumarin based...

A new coumarin based turn on fluorescent sensor (R1) was reported for the detection of highly hazardous Cd²⁺ with excellent selectivity and sensitivity without any interference of other metal ions. The single crystal X-ray structure analysis of the sensor showed the actual geometry of the molecule. For the first time, a Cd²⁺ induced FRET mechanism was observed and explained accordingly. Instant naked eye detection of Cd²⁺ through a sharp colour change signified the practical applicability of R1. The sensor of high quantum yield was applied in the intracellular detection of poisonous Cd²⁺ in living HeLa S3 cells.