Cell penetrating, mitochondria targeting multiply charged DABCO-cyanine dyes

Abstract We have prepared new series of lipophilic cyanine dyes equipped with several cationic quaternary ammonium moieties. This was achieved by introducing DABCO within the structures. Furthermore, to investigate the influence of the additional cationic charges on the cellular uptake, DABCO was quaternized with methyl group or alkyl piperidine cation. Spectroscopic and isothermal titration calorimetry studies as well as MTT assay and subcellular localization using confocal laser scanning microscopy revealed that some of the presented dyes combine low anti-proliferative effect with efficient cellular uptake, high affinity towards ds-DNA/RNA and remarkable fluorescent marking of mitochondria.