A pyrene-based dual chemosensor for colorimetric detection of Cu2+ and fluorescent detection of Fe3+

摘要

A pyrene based chemosensor was designed and synthesized. The pyrene fluorophore was connected with a pyridine unit through a Schiff base structure to give the sensor (L).Lwas tested with a variety of metal ions and exhibited high colorimetric selectivities for Cu2+and Fe3+over other ions. Upon binding with Cu2+or Fe3+,Lshowed an obvious optical color change from colorless to pink for Cu2+or orange for Fe3+over a wide pH range from 3 to 12. Moreover, the fluorescence ofLat 370nm decreased sharply after bonding with Fe3+, while other metal ions including Cu2+had no apparent interference. Thus, using such single chemosensor, Cu2+and Fe3+can be detected independently with high selectivity and sensitivity. The limits of detection toward Cu2+and Fe3+were 8.5 and 2.0μM, respectively. DFT calculation results also proved the formation of stable coordination complexes and the phenomenon of fluorescence quenching by Fe3+. Furthermore,Lwas also successfully used as a bioimaging reagent for detection of Fe3+in living cells.