Length sorting cut single wall carbon nanotubes by high performance liquid chromatography
Semi-preparative, HPLC based, size exclusion chromatography (SEC) was used to length sort single wall carbon nanotubes previously cut by an acid based process. In contrast to prior reports of nanotube length separation by gravity fed SEC, mean nanotube lengths in the present study were shorter than the controlled pore glass media pore diameter used (400 nm). The results indicate that prep scale HPLC can provide a viable method for efficient length separation with good resolution. Features observed in the chromatogram are attributed to a dependence of the light scattering efficiency on the lengths of the nanotubes relative to the wavelength of the light used for detection.
Abstract Peptide and protein samples are often complex mixtures that contain a number of individual compounds. The initial HPLC separation of such samples typically results in the poor resolution of one or more band pairs. Various means have been suggested tor varying separation selectivity so as to minimize this problem. In this study of a tryptic digest of recombinant human growth hormone, the simultaneous variation of temperature and gradient steepness was found to be a convenient and effective means of varying selectivity and optimizing the separation. The use of computer simulation greatly facilitated this investigation.