A novel phthalimide-rhodol-based ESIPT-FRET system for rapid colorimetric and ratiometric fluorescent detection of palladium

In this paper, a new colorimetric and ratiometric fluorescent probe was developed for rapid detection of palladium in aqueous solution under mild conditions. This probe is based on a novel phthalimiderhodol dyad, which has a unique ESIPT-FRET mechanism to give the desired ratiometric fluorescent signal changes. Optical sensing studies showed that this probe not only has high selectivity and sensitivity for palladium with a low detection limit of 31 nM, but also exhibits rapid and distinct colorimetric and ratiometric fluorescent signal changes with a large pseudo Stokes shift. In addition, the probe was successfully used for fluorescent imaging of palladium in living cells. Overall, this work provided a new ESIPT-FRET platform for development of ratiometric probes and a new attractive colorimetric and ratiometric fluorescent probe for detection of palladium. (C) 2017 Elsevier B.V. All rights reserved.