Uptake and localisation of rhenium fac-tricarbonyl polypyridyls in fluorescent cell imaging experiments

The synthesis of a series of rhenium fac tricarbonyl bisimine complexes and their application as lumophores in fluorescence imaging of yeast and human adenocarcinoma cells is reported. A wide range of complexes are synthesised with varying charges and lipophilicities, all of which have photophysical properties which make them suitable as cell imaging agents. After attempts to apply these as imaging agents in various strains of yeast which showed limited uptake, an investigation was undertaken of their applications as imaging agents in mammalian cells. In general the uptake was high and short-term toxicity and photobleaching appear to be low. The patterns of uptake and localisation are correlated with structural and electronic features of the complexes in an attempt to establish ground-rules for the design and application of rhenium complexes in imaging of eukaryotes.