DNA induced intense plasmonic circular dichroism of highly purified gold nanobipyramids

We report a strong and reversible CD response through the assembly of helical DNA and Au nanobipyramids (Au NBPs). Compared with common spherical Au nanoparticles or anisotropic Au nanorods, highly purified Au NBPs possess a more intense electromagnetic field and improved surface plasmon resonance. Thus, the assembly of DNA and Au NBPs exhibits an obviously enhanced plasmonic CD response. When the plasmonic CD is used for DNA detection, it shows high sensitivity and good reproducibility.