End-to-end self-assembly and colorimetric characterization of gold nanorods and nanospheres via oligonucleotide hybridization

We report end-to-end assembly for tuning the optical properties of a gold nanorod/sphere based on oligonucleotide hybridization. The rationale behind the selection of the mercaptoalkyloligonucleotide molecule is based on the fact that the thiol group binds to the ends of the nanorods, which further assemble in an end-to-end fashion through hybridization with the target oligonucleotide. A highly selective, colorimetric polynucleotide detection method based on mercaptoalkyloligonucleotide-modified gold nanorod/sphere probes is also reported.