Fluorescent zwitterionic iridium complexes have been rarely reported. In this work, four fluorescent zwitterionic cyclometalated iridium complexes bearing different sulfonated iminopyridine ligands (Ir1–Ir4) were synthesized. The solid-state molecular structure of Ir1 was established by X-ray crystallography. These zwitterionic complexes are very stable in aqueous solution and have a detectable fluorescence. The structure-activity relationship toward cancer cells was observed for these complexes. Further, the fluorescence properties of these zwitterionic complexes make it possible to determine their microscopic mechanism by the cell imaging. It is noteworthy that complex Ir3 can specifically and effectively target lysosomes and induce cell death by damaging lysosomes Further, the energy-dependent pathway was involved in the uptake of Ir3 in cancer cells. In addition, the modes of cell death were also studied through flow cytometry experiments. It seems that Ir3 displayed their biological efficacy by cell-cycle arrest and the induction of cell apoptosis.

很少报道荧光两性离子铱配合物。在这项工作中，合成了四个带有不同磺化亚氨基吡啶配体（Ir1 - Ir4）的荧光两性离子环金属化铱配合物。Ir1的固态分子结构通过X射线晶体学确定。这些两性离子络合物在水溶液中非常稳定，并具有可检测的荧光。对于这些复合物，观察到了与癌细胞的构效关系。此外，这些两性离子络合物的荧光性质使得可以通过细胞成像确定其微观机理。值得注意的是，复杂的Ir3可以特异性地和有效地靶向溶酶体并通过破坏溶酶体来诱导细胞死亡。此外，能量依赖性途径与癌细胞中Ir3的摄取有关。此外，还通过流式细胞术实验研究了细胞死亡的模式。Ir3似乎通过细胞周期停滞和诱导细胞凋亡显示出其生物学功效。