Zn(II) complexes based on functional organic ligands: Two-photon activity, theoretical calculation and bioimaging

An organic ligand (3-[4-(diphenylamino)styryl] pyridine, L) was synthesized. By complexation of L with ZnBr2 and Zn(NCS)2 respectively in methanol and dichloromethane, two complexes ZnBr2L2 (dye1) and Zn(NCS)2L2 (dye2) were prepared. The two dyes exhibit good one- and two-photon fluorescence performance with high fluorescence quantum yields and large two-photon absorption cross section values. The mechanism of one-photon absorption and one-photon excited fluorescence based on computational results was obtained by TDDFT/CAM-B3LYP method. The results of living cell imaging experiments exhibit their compatibility in cytoplasm of HepG2 cells and show their potential in fluorescence microscopy bioimaging