Abstract: The present invention is directed toward methods and devices for analyzing populations of single-wall carbon nanotubes (SWNTs) on the basis of their fluorescence properties and the comparison of said properties to fluorescence profiles of pre-determined SWNT compositions. Generally, such analyzing yields information about the composition of the SWNTs within said population. Such information includes, for example, the relative abundances of semiconducting SWNTs, the diameter distribution of such SWNTs, and the relative abundances of one or more particular SWNT species—as identified by one or more specific nanotube indices (n,m). The methods and devices of the present invention provide for the analysis of SWNT compositions in a rapid and efficient manner.

Abstract: The present invention is directed toward fluorescent inks and markers comprising carbon nanotubes. The present invention is also directed toward methods of making such inks and markers and to methods of using such inks and markers, especially for security applications (e.g., anti-counterfeiting). Such inks and markers rely on the unique fluorescent properties of semiconducting carbon nanotubes.

Abstract: The invention relates to a process for sorting and separating a mixture of (n, m) type single-wall carbon nanotubes according to (n, m) type. A mixture of (n, m) type single-wall carbon nanotubes is suspended such that the single-wall carbon nanotubes are individually dispersed. The nanotube suspension can be done in a surfactant-water solution and the surfactant surrounding the nanotubes keeps the nanotube isolated and from aggregating with other nanotubes. The nanotube suspension is acidified to protonate a fraction of the nanotubes. An electric field is applied and the protonated nanotubes migrate in the electric fields at different rates dependent on their (n, m) type. Fractions of nanotubes are collected at different fractionation times. The process of protonation, applying an electric field, and fractionation is repeated at increasingly higher pH to separated the (n, m) nanotube mixture into individual (n, m) nanotube fractions.