DNA-Based Carbon Nanotube Purification
DNA-assisted separation of single-walled carbon nanotube via ion-exchange chromatography has demonstrated exceptional recognition capability of this approach. A set of DNA sequences capable of purifying 12 (n, m) single-chirality nanotubes (shown right) has been identified after systematic search of the DNA library. It is shown that the length and the sequence of DNA and the experimental condition can all influence the separation outcome. Therefore, tuning these parameters has the potential of discovering more single-chirality nanotube species and optimizing the resolution and the yield.
The mechanism of the DNA-based separation is not entirely clear; however, the ordered structure of DNA wrapping around nanotube is believed to hold the key. Therefore, investigating DNA–nanotube interaction becomes vital to unveil the mechanism of the separation and other interesting properties of DNA and nanotube.
Carbon Nanotube Environmental and Health Safety (EHS)
The accurate evaluation of the toxicity of carbon nanotube, especially to biological molecule, is a very important field. The oxidative stress experienced by DNA molecules in the presence of carbon nanotube can inform us of the safety of the material in long term and reveal structural information of DNA-nanotube hybrid.
There are many more exciting Nanotube Metrology projects in the Complex Fluids Group of Polymers Division. Please refer to these links for more information.
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