Formation of Au Nanowires by DNA Molecules as a Template

We developed a simple technique to form An nanowires (AuNWs) by the conjugation of 2-aminoethanthio-capped gold nanoparticles (AET-AuNPs) and DNA molecules immobilized on 3-aminopropyltriethoxysilane (APS)-coated Si wafers. In this technique, the metallization process involved three steps: (1) DNA molecules were immobilized on the APS-coated Si substrate, (2) AET-AuNPs were formed via a strong chemical reaction between the thiol (-SH) group of AET and the AuNPs, and (3) AuNWs were then formed by the interaction between DNA and the AET-AuNPs. We investigated the effects of the mole ratio (i.e., AuNPs/AET) and the incubation time in controlling the distance between AuNPs, and found that the incubation time was a very important factor for the formation of AuNWs.