Studies of the interactions of 4-carboxyl-2,6-dinitrophenylazohydroxynaphthalenes with CT-DNA in aqueous medium

► Dyes-DNA complex formation studied at two temperatures ► ds-DNA binds dyes based on their structure. ► Two congeners gave 1:1 mole ratio in binding to DNA. ► Thermodynamic considerations established mode of binding. ► One congener utilised electrostatic interactions in binding.