Hydrogen bond rich supramolecular systems towards theranostics
University of New Brunswick
Iridium complexes have many applications: bioimaging, functional materials (e.g. photovoltaic cells), synthetic catalysts, and, due to their high photoluminescence, organic light emitting diodes (OLEDs). Hydrogen-bonding (H-bonding) is integral to the design of sophisticated functional organic materials because different assembly patterns of Hbond acceptor and donor atoms lead to varying association strengths. Cyclometalated iridium (III) complexes that contain self-assembling H-bonding motifs provide a colourtuning solution to inner-sphere synthetic modifications. In the current work, a DNA-like H-bonding array is used to influence the emissive properties of eight cyclometalated iridium (III) complexes via host-guest chemistry. DNA/RNA nucleobases have naturally occurring H-bonds that mimic an organic guest molecule (pyrimido[4,5-c]isoquinolin-3- amine), making them suitable binding partners for the iridium (III) host complexes. The association strengths of these nucleobase interactions will help to predict how the colourful iridium complexes will perform as potential theranostic (i.e. therapeutic and diagnostic) tools.