Adsorption of Deoxyribonucleic Acid on Nanocrystalline Titanium and Cerium Dioxide Surfaces

Adsorption of deoxyribonucleic acid on the surfaces of nanosized titanium and cerium dioxides from aqueous solutions has been studied as depending on pH and adsorbate concentration. The comparison of the data on the adsorption of DNA, an inorganic phosphate, and nucleotides that compose nucleic acid molecules, as well as the states of the surface functional groups of the metal oxides, has revealed that the double-stranded DNA is mainly adsorbed with the participation of the phosphate backbone of its molecule. The heterocyclic bases of nucleotides are not involved in the adsorption process. The approach of DNA to the oxide surface under the action of electrostatic attraction promotes other types of interactions, e.g., dispersion interaction and hydrogen bonding.