A novel two-photon fluorescent probe for efficiently detecting Zn2+ and Cd2+ ions

A novel two-photon fluorescent probe (ZC-F2) for selective recognizing Zn 2+ and Cd 2+ was designed and synthesized. By tuning the intramolecular charge transfer (ICT), ZC-F2 can recognize Zn 2+ and Cd 2+ through different emission colors in acetonitrile , the detection limit of Zn 2+ and Cd 2+ are 11.25 nM and 1.80 nM respectively. Moreover, ZC-F2 exhibits strong two-photon fluorescence emission when being excited by a femtosecond laser in the range of 700–860 nm, and its two-photon absorption (TPA) cross-section is studied. The cell-imaging experiments show that ZC-F2 has high sensitivity to Zn 2+ and Cd 2+ , indicating its potential applications in environmental and biological detection.