Figure 6.

Binding isotherms of the binding of 1 to calf thymus DNA in 10 mM phosphate buffer. In order to dissolve the ligand in water, equal aliquots of concentrated stocks in organic solvents miscible with water were added to aqueous solutions of DNA in different concentrations. In panel (a), the organic solvent was DMSO and the final ligand concentration was 20 μM; in panel (b), DMF was used and the ligand was added to a final concentration of 15 μM. In both the experiments, the volume-to-volume concentration of organic solvent in phosphate buffer was 1:150.