A comparison of human telomeric G-quadruplex-double stranded DNA interactions of newly synthesized Pt(II) complex of benzimidazole based ligand

The synthesis, characterization, double stranded (ds-DNA) and G-quadruplex DNA (G-DNA) binding affinities of a new Pt(II) complex of a new benzimidazole based ligand 6-(1<i>H</i>-Imidazol-4-yl)-1,7-dihydroimidazo[4,5-f]benzimidazol-2-ol (idbo) is reported. The interactions of Pt(II) complex with ds-DNA and G-DNA have been studied by UV-Vis titration, UV thermal melting, fluorescent intercalator displacement (FID), competition dialysis and the findings were compared with the other known G-DNA binding compounds. The metal complex binds both G-DNA and ds-DNA according to UV titration results. Uv thermal melting studies show that the new Pt(II) complex stabilize G-quadruplex structure. A high G-DNA selectivity is calculated with FID results. Also, competition dialysis results prove the 1.6 selectivity on G-DNA binding of complex over ds-DNA.