Directed Self-Assembly of Carbon Nanotubes into Microspheres

Carbon nanotube microspheres (CNMs) were prepared using the inherent self-organizing characteristics of the nanotubes that primarily rely on electrostatic interaction, not the assistance of any polymers or surfactants. They permit significant linkage with a variety of chemical species such as biomolecules, metal nanoparticles, and fluorescent dyes. The cationic species of guest molecules facilitate individual nanotubes to coalesce and merge together into new colloidal structures. These novel CNMs create new technical opportunities for a wide range of applications. In particular, the capability of conjugating with a broad number of chemical species would be a fundamental basis for development of bio-electronics and biomedical applications.