In vitro cytotoxicity of a library of BODIPY-anthracene and -pyrene dyads for application in photodynamic therapy

The facile synthesis and in vitro activity of a library of heavy atom-free BODIPY-anthracene, -pyrene dyads ( BAD-13–BPyrD-19 ) and a control ( BODIPY 20 ) are reported. We demonstrate that singlet oxygen produced from dyad triplet states formed from charge-separated states is sufficient to induce cytotoxicity in human breast cancer cells (MDA-MB-468) at micromolar concentrations. The compounds in this series are promising candidates for photodynamic therapy, especially BAD-17 which displays significant photo-cytotoxicity (15% cell viability) at a concentration of 5 × 10 −7 M, with minimal toxicity (89% cell viability) in the absence of light.