Nanotubes sort out their left and right


Left- and right-handed carbon nanotubes can be separated from one another, according to a paper. Although nanotubes have previously been sorted on the basis of their diameter or length, this method is the first to discriminate between those with opposite helical twists.
Some molecules, which are known as ‘chiral’, can exist as mirror-image forms that cannot be superimposed on each other. Louis Pasteur was, in 1849, the first to separate such molecules, by meticulously sorting asymmetric crystals of tartaric acid by hand, using tweezers and a microscope. Following in his footsteps, Naoki Komatsu and co-workers designed pairs of chemical ‘nano-tweezers’ that can selectively pluck either left- or right-handed nanotubes from a mixture.
The ability to separate carbon nanotubes — one of nanotechnology’s most promising building blocks — in this way will lead to a better understanding of their optical properties, and may offer unique opportunities for photonics and quantum optics.
Author contact:
Naoki Komatsu (Shiga University of Medical Science, Otsu, Japan)
Tel: +81 77 548 2102; E-mail: nkomatsu@belle.shiga-med.ac.jp