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DNA-Controlled Carbon Nanotube Partition in Polymer Aqueous Two-Phase Systems



Geyou Ao, Constantine Y. Khripin, Ming Zheng


Sorting single-wall carbon nanotubes (SWCNTs) of different chiralities is both scientifically interesting and technologically important. Recent studies have shown that polymer aqueous two-phase extraction is a very effective way to achieve nanotube sorting. However, published works so far have only demonstrated separation of surfactant-dispersed SWCNTs, and the mechanism of chirality dependent SWCNT partition is not well-understood. Here, we report a systematic study of spontaneous partition of DNA-wrapped SWCNTs in several polymer aqueous two-phase systems. We show that partition of DNA-SWCNT hybrids in a given polymer two-phase system is strongly sequence-dependent, and can be further modulated by salt and polymer additives. With proper combination of DNA sequence, polymer two-phase system, and partition modulators, as many as 15 single-chirality nanotube species have been effectively purified from a synthetic mixture. As an attempt to provide a unified partition mechanism of SWCNTs dispersed by surfactants and by DNA, we present a qualitative analysis of solvation energy for SWCNT colloids in a polymer-modified aqueous phase. Our observation and analysis highlight the sensitive dependence of hydration energy on the spatial distribution of hydrophilic functionalities.
Journal of the American Chemical Society


single-wall carbon nanotubes, separation, solvation energy


Ao, G. , Khripin, C. and Zheng, M. (2014), DNA-Controlled Carbon Nanotube Partition in Polymer Aqueous Two-Phase Systems, Journal of the American Chemical Society (Accessed April 13, 2024)
Created June 28, 2014, Updated January 19, 2023