Platinum(II)‐Based Optical Probes for Imaging Quadruplex DNA Structures via Phosphorescence Lifetime Imaging Microscopy

Abstract

G‐quadruplex DNA is a non‐canonical structure that forms in guanine‐rich regions of the genome. There is increasing evidence showing that G‐quadruplexes have important biological functions, and therefore molecular tools to visualise these structures are important. Herein we report on a series of new cyclometallated platinum(II) complexes which, upon binding to G‐quadruplex DNA, display an increase in their phosphorescence, acting as switch‐on probes. More importantly, upon binding to G‐quadruplexes they display a selective and distinct lengthening of their emission lifetime. We show that this effect can be used to selectively visualise these structures in cells using Phosphorescence Lifetime Imaging Microscopy (PLIM).

Introduction of a mesityl substituent on pyridyl rings as a facile strategy for improving the performance of luminescent 1,3-bis-(2-pyridyl)benzene platinum(ii) complexes: a springboard for blue OLEDs

“…Platinum complexes have attracted much attention for many applications such as nonlinear optics, 1–6 bioimaging, 7–14 sensing, 15–17 and electroluminescent devices. 18–38 Indeed, among a large number of organometallic materials, phosphorescent platinum( ii ) complexes have gained interest due to the important spin–orbit coupling associated with the metal which promotes intersystem crossing, and therefore the emission of light from triplet excited states, a behavior that is further improved by the presence of platinum–carbon bonds.…”