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Thermodynamically controlled separation of polyvalent 2-nm gold nanoparticle-oligonucleotide conjugates.

ABSTRACT: We describe the synthesis of small (2-nm diameter) gold nanoparticles densely functionalized with thiolated DNA (DNA-Au NPs) and a method to separate these particles from excess free DNA after synthesis. The separation method utilizes the thermodynamically enhanced binding properties of 2-nm DNA-Au NPs, compared to free excess DNA, to selectively hybridize these small particles to larger (15-nm diameter) DNA-Au NPs and form aggregates that can be isolated by simple centrifugation. These 2-nm DNA-Au NPs are obtained in a 46% overall yield, have a high surface coverage of DNA (64.8 +/- 6.4 pmol/cm2), and as a result, exhibit increased melting temperatures and cooperative melting properties.

SUBMITTER: Lee JS

PROVIDER: S-EPMC8281389 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature

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Thermodynamically controlled separation of polyvalent 2-nm gold nanoparticle-oligonucleotide conjugates.

Lee Jae-Seung JS Seferos Dwight S DS Giljohann David A DA Mirkin Chad A CA

Journal of the American Chemical Society 20080328 16

We describe the synthesis of small (2-nm diameter) gold nanoparticles densely functionalized with thiolated DNA (DNA-Au NPs) and a method to separate these particles from excess free DNA after synthesis. The separation method utilizes the thermodynamically enhanced binding properties of 2-nm DNA-Au NPs, compared to free excess DNA, to selectively hybridize these small particles to larger (15-nm diameter) DNA-Au NPs and form aggregates that can be isolated by simple centrifugation. These 2-nm DNA ...[more]

PMID: 18370386

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