pH-responsive aldehyde-bearing cyclometalated iridium(Ⅲ) complex for tracking intracellular pH fluctuations under external stimulation

作者：Manping Qian; Danyang Zhang; Hetong Qi; Xuebing Yang; Guanjun Yin; Chengxiao Zhang; Jianzhong Guo; Honglan Qi^*

来源：Chinese Chemical Letters, 2023, 34(02): 276-280.

Intracellular p H undertakes critical functions in various biological and pathological processes. It is important to monitor intracellular p H fluctuations for understanding physiological and pathological processes.Here, one aldehyde-bearing cyclometalated iridium(Ⅲ) complex([(4-pba)2Ir(dcphen)]PF6, 4-pba = 4-(2-pyridyl) benzaldehyde, dcphen = 4,7-dichloro-1,10-phenanthroline, probe 1) was synthesized and used to track intracellular p H fluctuations. Probe 1 displayed p H-dependent luminescence property in p H range of 1.81–6.81 with an evaluated p Kavalue of 4.30 in BR buffer-DMSO(v:v = 99:1). An intramolecular hydrogen bonds assisted p H-responsive mechanism was proposed for the p H-responsive behavior of probe1. Probe 1 was successfully applied for imaging and tracking p H fluctuations in He La cells under external stimulation with fast response time, good photostability as well as low cytotoxicity and high cell permeability. This work demonstrates that aldehyde-bearing cyclometalated iridium(Ⅲ) complex can be used as alternative p H-responsive probe for real-time tracking intracellular p H fluctuations, which provides a strategy for the design of p H-responsive probe in versatile applications.

• 单位
  生命分析化学国家重点实验室; 陕西师范大学