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PubMed · 15986644

Complex formation between cationically modified gold nanoparticles and DNA: an atomic force microscopic study.

Munia Ganguli·J Venkatesh Babu·Souvik Maiti
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Abstract

Atomic force microscopy has been used for direct visualization of the wrapping of DNA around 30-nm-sized functionalized gold nanoparticles for the first time. The morphology of the complexes seems to be dictated by the relative concentration of the nanoparticles and DNA. A higher concentration of the former leads to the formation of a network of nanoparticles assembled on DNA. This assembly pattern seems to be significantly different from the manner in which cationically modified gold nanoparticles of smaller size (< 5 nm) arrange linearly on DNA, as shown in the literature. A DNA-gold nanoparticle can be developed as a model system for in vitro studies on the mechanism of DNA condensation and also for developing novel methods of nanoparticle self-assembly on the DNA template.

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Munia Ganguli, J Venkatesh Babu, Souvik Maiti. 2004-06-22. Complex formation between cationically modified gold nanoparticles and DNA: an atomic force microscopic study.. https://doi.org/10.1021/la036049a

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