Synthesis and thermodynamically controlled anisotropic assembly of DNA-silver nanoprism conjugates for diagnostic applications

We have synthesized DNA-silver nanoprism conjugates using the thiol-silver interaction and have assembled them into anisotropic structures with distinctive optical properties simply by controlling thermodynamic conditions. The reversible assembly formation takes advantage of the natural anisotropic architecture of the silver nanoprisms and the cooperative properties of their DNA conjugates. The anisotropic assemblies have been observed not only ex situ by TEM but also in situ in a solution by UV-vis spectroscopy. We have further investigated biodiagnostic applications of the DNA-silver nanoprism conjugates for the colorimetric and quantitative detection of DNA with high selectivity and sensitivity in the full visible range based upon their unique distant-dependent optical properties.