A Novel Logic Gate Fluorescent Sensor for the Sequential Detection of Cd2+ and Pyrophosphate Anion and Application in Cell Imaging

A novel fluorescent sensor L based on 8-hydroxyquinoline (8-HQ) has been designed and synthesized. The sensor L displayed excellent sensitivity specific toward Cd2+ and pyrophosphate anion (PPi), respectively. The fluorescence emission peak at 537 nm was quenched when Cd2+ was added to the DMSO/H2O (V/V=1/1, 0.01 mol/L, Hepes-HCl buffer, pH=7.20) solution of sensor L and the detection limit was as low as 5.87x10(-8) mol/L. The 1:1 stoichiometry was verified by Job's plot and mass spectrum, and the association constant was obtained to be 4.37x10(4) L/mol. The further study found that the L-Cd2+ system has high selectivity for detection of PPi by ligand replacement method and L could be used as a logic gate fluorescence sensor. In addition, the sensor L was employed for imaging the Cd2+ and PPi in living cells.