Direct observation by time-resolved infrared spectroscopy of the bright and the dark excited states of the [Ru(phen)₂(dppz)]²⁺ light-switch compound in solution and when bound to DNA.

ABSTRACT: The [Ru(phen)₂(dppz)]²⁺ complex (1) is non-emissive in water but is highly luminescent in organic solvents or when bound to DNA, making it a useful probe for DNA binding. To date, a complete mechanistic explanation for this "light-switch" effect is still lacking. With this in mind we have undertaken an ultrafast time resolved infrared (TRIR) study of 1 and directly observe marker bands between 1280-1450 cm^-1, which characterise both the emissive "bright" and the non-emissive "dark" excited states of the complex, in CD₃CN and D₂O respectively. These characteristic spectral features are present in the [Ru(dppz)₃]²⁺ solvent light-switch complex but absent in [Ru(phen)₃]²⁺, which is

SUBMITTER: Poynton FE 

PROVIDER: S-EPMC6005197 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature