Designed diblock oligonucleotide for the synthesis of spatially isolated and highly hybridizable functionalization of DNA-gold nanoparticle nanoconjugates.

Hao Pei, Fan Li, Ying Wan, Min Wei, Huajie Liu, Yan Su, Nan Chen, Qing Huang, Chunhai Fan

Laboratory of Physical Biology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.

Journal of the American Chemical Society 2012 Jul 25

filter terms:

Conjugates of DNA and gold nanoparticles (AuNPs) typically exploit the strong Au-S chemistry to self-assemble thiolated oligonucleotides at AuNPs. However, it remains challenging to precisely control the orientation and conformation of surface-tethered oligonucleotides and finely tune the hybridization ability. We herein report a novel strategy for spatially controlled functionalization of AuNPs with designed diblock oligonucleotides that are free of modifications. We have demonstrated that poly adenine (polyA) can serve as an effective anchoring block for preferential binding with the AuNP surface, and the appended recognition block adopts an upright conformation that favors DNA hybridization. The lateral spacing and surface density of DNA on AuNPs can also be systematically modulated by adjusting the length of the polyA block. Significantly, this diblock oligonucleotide strategy results in DNA-AuNPs nanoconjugates with high and tunable hybridization ability, which form the basis of a rapid plasmonic DNA sensor.

Citation

Hao Pei, Fan Li, Ying Wan, Min Wei, Huajie Liu, Yan Su, Nan Chen, Qing Huang, Chunhai Fan. Designed diblock oligonucleotide for the synthesis of spatially isolated and highly hybridizable functionalization of DNA-gold nanoparticle nanoconjugates. Journal of the American Chemical Society. 2012 Jul 25;134(29):11876-9