NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
High Resolution Length Fractionation of Surfactant Dispersed Carbon Nanotubes
Published
Author(s)
Constantine Y. Khripin, Xiaomin X. Tu, Jeffrey A. Fagan, Ming Zheng
Abstract
Length fractionation of colloidal carbon nanotube dispersions is required for many studies. Size- exclusion chromatography (SEC) has been reported as a reliable method for high resolution length fractionation of DNA-dispersed single-wall carbon nanotubes (SWCNTs), but has not found use for more commonly used bile salt dispersed SWCNTs due to dispersion stability and quality problems. Here we describe the extension of SEC for high resolution length fractionation of bile salt dispersed SWCNTs using porous silica-based beads as the stationary phase and bile salt solution as the mobile phase, and demonstrate that the prior difficulties with the method can be readily overcome. Further, we use the new SEC method to length-fractionate bile salt dispersed SWCNTs pre-purified by ultracentrifugation methods. Unlike length-fractionated samples obtained from the raw material, and all length-fractionated samples previously reported, these double-purified samples show little dependence of optical absorbance spectra on length. Comparing length fractions of 360 nm and 130 nm length, the baseline changes by
Khripin, C.
, Tu, X.
, Fagan, J.
and Zheng, M.
(2012),
High Resolution Length Fractionation of Surfactant Dispersed Carbon Nanotubes, Analytical Chemistry, [online], https://doi.org/10.1021/ac303349q
(Accessed October 10, 2025)