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Single-step total fractionation of single-wall carbon nanotubes by countercurrent chromatography



Ming Zheng, Min Zhang, Constantine Y. Khripin, Jeffrey Fagan, Yoichiro Ito


Development of simple processes to fractionate synthetic mixtures of single-wall carbon nanotubes (SWCNTs) into individual species is crucial to many applications. Existing methods for single- chirality SWCNT purification are cumbersome, often requiring multiple steps and different conditions for different species. Here, we report a method to achieve total fractionation of a synthetic SWCNT mixture by countercurrent chromatography (CCC), resulting in purification of many single-chirality SWCNT species in a single run. This method is based on tunable partition of so-dium deoxycholate dispersed SWCNTs in polyethylene glycol / dextran aqueous-two phase system. By running the mobile phase with 0.02% of sodium deoxycholate and a gradient of sodium dodecyl sulfate from 0.1% to 0.7% (w/w), we observe clear diameter dependent elution, with 90% total recovery. Among all the fractions collected, a number of them are en-riched in single-chirality (9,4), (7,5), (7,6), (8,3), (6,5) species, while most of the remaining ones contain no more than 2-3 major species. We also observe strong (n,m) dependent elution peak width, most likely due to enantiomer-resolved partition. These results demonstrate CCC as an effective way to obtain high purity (n, m) species, and suggest the potential of CCC as an analytical tool for chirality distribution mapping of synthetic mixtures.
Analytical Chemistry


carbon nanotube, separation


Zheng, M. , Zhang, M. , Khripin, C. , Fagan, J. and Ito, Y. (2014), Single-step total fractionation of single-wall carbon nanotubes by countercurrent chromatography, Analytical Chemistry (Accessed May 28, 2024)


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Created April 15, 2014, Updated January 19, 2023