Multifunctional BODIPY derivatives to image cancer cells and sense copper(ii) ions in living cells

Abstract

Two multifunctional colorimetric and fluorescent chemosensors were synthesized by the conjugation of BODIPY (4,4-difluoro-1, 3, 5, 7-tetramethyl-4-bora-3a, 4a-diaza-s-indacene) and di(2-picolyl)amine with benzyl groups (para-substituted, L1; meta-substituted, L2) as spacers, for selectively sensing copper(II) ions in preference to a variety of other common metal ions in aqueous media. The two analogous compounds exhibit different cytotoxic behaviour and attenuate mitochondrial membrane potentials in HepG-2 cells. In vitro bioassay results demonstrate that only L2 causes the decrease of mitochondrial membrane potentials in HepG-2 cells with low toxicity. Furthermore, fluorescence imaging in vitro confirms that L2 is a low toxicity chemosensor for copper(II) ions in living cells.