Inhibition of DNA hybridization by small metal nanoparticles.

The inhibition of DNA hybridization by small metal nanoparticles has been examined in detail. DNA melting point analysis showed that the oligonucleotides adsorb strongly and nonspecifically on small metal nanoparticles, inhibiting the hybridization of complementary DNA sequences in common buffered solutions. The nonspecific interaction is even strong enough to disrupt pre-existing hydrogen bonds in short double-stranded DNA. The nonspecific interaction could be weakened by increasing the particle size. As an example, a core-shell assisted method was used to successfully assemble Pt nanoparticles by DNA hybridization that could not be done otherwise.