Guangcun Shan
University of Hong Kong, Hong Kong
Title: Ultralong luminescent transition metal complexes as biomolecular probes and bioimaging reagents
Biography
Biography: Guangcun Shan
Abstract
Most fluorescent biological probes and bio-imaging reagents developed thus far are organic dyes. It is commonly believed that transition metal complexes are highly toxic and thus not suitable for biological applications, especially where living systems are concerned. It has been shown that luminescent transition metal complexes are attractive candidates to probe biomolecules and image live cells and animals, because they show longer-lived emission, higher photo stability and minimal self-quenching. However, the task of generating excited states with long lifetimes has been met with limited success, owing to the ultrafast deactivation of the highly active excited states5. In this talk, we present a design rule that can be used to tune the emission lifetime of a wide range of luminescent organic molecules, based on effective stabilization of triplet excited states through strong coupling in H-aggregated molecules. Based on first-principle design, our data revealed that luminescence lifetimes up to 1.35 s, which are several orders of magnitude longer than those of conventional organic fluorophores, can be realized under ambient conditions. These results outline a fundamental principle to design organic fluorescent molecules with extended lifetimes of excited states, providing a major step forward in expanding the scope of organic phosphorescence applications.