Iridium(III) complexes with 1,10-phenanthroline-based NN ligands as highly selective luminescent G-quadruplex probes and application for switch-on ribonuclease H detection

A systematic study was performed to investigate the relationship between molecular structure and G-quadruplex sensing ability for a series of structurally related cyclometallated iridium(III) complexes. The novel complex 7 was used to construct a label-free luminescent switch-on G-quadruplex-based assay for RNase H activity in buffered solution. The constructed detection platform was simple, low-cost and highly sensitive for RNase H, and functioned effectively in the presence of cellular debris.