DNA Integration with Silver and Gold Nanoparticles: Enhancement of DNA Optical Anisotropy.

DNA integration with silver and gold nanoparticles was carried out by the chemical reduction of silver and gold ions after the formation of their complexes with high molecular DNA in solution. It is shown that, for a good association of DNA with nanoparticles, the ions of silver and gold should be linked with DNA bases rather strongly. The proposed model of gold interaction with DNA is the coordination of gold to N7 guanine in a major groove followed by the transformation of the GC pair to Hoogsteen's type pairing, in which the gold atom is located between the bases and is bonded simultaneously to N7 guanine and N3 cytosine.