Changes in Oligonucleotide Conformation on Nanoparticle Surfaces by Modification with Mercaptohexanol

The conformation of thiol-linked oligonucleotides on the surface of Au nanoparticles was controlled by treatment with 6-mercapto-1-hexanol (MCH). MCH displaces noncovalent base adsorption to the surface, changing the oligo conformation on the Au surface. By controlling MCH concentration and reaction time, a change in effective size (Deff) of the Au−DNA conjugates and improved hybridization ability was observed, suggesting a reduced nonspecific adsorption of the oligo to the Au.