Highly Selective Recognition of Pyrophosphate by a Novel Coumarin-Iron (III) Complex and the Application in Living Cells

In this paper, a novelNL-Fe3+ensemble was designed as a fluorescent chemosensor for highly selective detection of pyrophosphate (PPi) in DMSO/H2O (2:8/v:v, pH = 7.2) solution and living cells.NLshowed a strong affinity for Fe3+and was accompanied by obvious fluorescence quenching. Upon the addition of PPi to the generatedNL-Fe3+ensemble, the fluorescence and absorption spectra were recovered completely. Spectroscopic investigation showed that the interference provoked by common anions such as adenosine-triphosphate (ATP), adenosine diphosphate (ADP), and phosphates (Pi) can be ignored. The detection limit ofNL-Fe3+to PPi was calculated to be 1.45 × 10−8M. Intracellular imaging showed thatNL-Fe3+has good membrane permeability and could be used for the detection of PPi in living cells. A B3LYP/6-31G(d,p) basis set was used to optimizeNLandNL-Fe3+complex.Keywords:coumarin;Fe(III);pyrophosphate;cells imaging