Synergistic effects of adsorption and interaction of DNA with mixed monolayers of anionic amphiphile and chromium(III) complexes

Investigations have been carried out to probe the interactions between double stranded DNA and non-amphiphilic chromium(III) complexes, [Cr(en)3]3+ and [Cr(phen)3]3+ (en-ethylenediamine, phen-1,10 phenanthroline) in mixed monolayers with dihexadecyl phosphate (DHP). Under the experimental conditions, the results show that there is a specific binding mode between [Cr(en)3]3+ and DNA at air/water interface based on adsorption followed by a strong binding of [Cr(en)3]3+ to DNA based on H-bonding. In case of [Cr(phen)3]3+, the results indicate that after initial adsorption of DNA to the metal complex, partial intercalation of Cr(phen)33+ takes place in the strands of DNA.