Preliminary investigation of Ru(II) complexes bearing nile red chromophores for photodynamic therapy

Two previously investigated Ru(II) triplet photosensitisers (PS) ( [Ru-2ENR][(PF 6 ) 2 ] and [Ru-3ENR][(PF 6 ) 2 ] ) comprising a bipyridyl frame and acetylene appended Nile red chromophore, were converted to their chloride salts for cytotoxicity and phototoxicity measurements. SKBR3-cell lines were used to evaluate the photodynamic activity of the compounds. Irradiation ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m1"><mml:mrow><mml:mi mathvariant="bold-italic">λ</mml:mi></mml:mrow></mml:math> ex 630 nm; 15 min; 33 J cm −2 ) at a non-toxic concentration of 10 nM, [Ru-2ENR][(PF 6 ) 2 ] and [Ru-3ENR][(PF 6 ) 2 ] induced a reduction in metabolic activity by 60% and 30% respectively.