A fluorescent sensor, N-(quinolin-8-yl)-2-(quinolin-8-yloxy)acetamide (HL), based on 8-aminoquinoline and 8-hydroxyquinoline platforms has been synthesized. This sensor displays high selectivity and sensitive fluorescence enhancement to Cd(2+) in ethanol. Moreover, sensor HL can distinguish Cd(2+) from Zn(2+) via two different sensing mechanisms (photoinduced electron transfer for Cd(2+); internal charge transfer for Zn(2+)). The composition of the complex Cd(2+)/HL or Zn(2+)/L(-) has been found to be 1:1, based on the fluorescence/absorption titration and further confirmed by X-ray crystallography.

A merocyanine-based highly selective colorimetric and ratiometric fluorescent probe is described for Cys detection in water and diluted deproteinized human serum. Upon reaction with Cys in aqueous buffer solution, the probe showed a dramatic color change from faint yellow to pink and remarkable ratiometric fluorescence enhancement signals were also observed, which are ascribed to an intramolecular charge transfer (ICT) process. This strategy was based on modulating the merocyanine π-electron system by conjugation and removal of the acrylate group to release the chromophore group, resulting in a specific colorimetry and fluorescence response. The probe has low cytotoxicity and good cell permeability. It is readily employed for assessing the change of the intracellular Cys level.

A new oxidative C-O bond cleavage reaction-based probe FluHMPP was designed and prepared. FluHMPP displays excellent selective turn-on fluorescence response for Cu(II) in aqueous solution under visible light excitation. The cleavage products are fully characterized. Fluorescein fragment is further oxidized to highly fluorescent MFME (3'-O-methylfluorescein methyl ester), and benzyl ether of imine fragment has been transformed to carboxyl. Confocal microscopy experiments have demonstrated that FluHMPP could also be used in live cells for the detection of Cu(II).

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Four dinuclear lanthanide mesocates were fabricated through a spontaneous self‐assembly method, and the formation of these complexes was well studied by their absorption and emission spectra. These stable complexes were also found to exhibit superior performance in catalyzing the coupling reaction between epoxides and CO2 with excellent recyclability. Moreover, the catalysts could be prepared on large scale. Moreover, the Yb and Lu complexes featured emissions in the near‐infrared and visible regions, respectively, and their intensities and lifetimes could be used for identification purposes. Thus, this new approach can be used to construct promising lanthanide complexes as efficient catalysts and it identifies the possibility to better study a catalytic reaction with a luminescent catalyst.