Posted: August 7, 2006

Successful development of massive synthesis of white organic nanotubes

(Nanowerk News) Until now, mass-production of organic nanotubes has been very difficult technically, because a large amount of water solvent has been needed for the synthesis of self-assembled organic nanotubes from amphiphilic molecules.Researchers at National Institute of Advanced Industrial Science and Technology (AIST) in Japan have developed a convenient mass-synthesis method for nanotubes which uses less than one thousandth of the solvent used in conventional methods, and the time required for the drying process is only a few hours. Since the nanotubes we have developed enable the encapsulation of functional substances (proteins, metal nanoparticles, etc.) larger than 10 nm, which have been impossible to encapsulate until now, applications to the slow release of medicines and health foods are expected.
The High Axial-Ratio Nanostructure Fabrication Team of the Nanoarchitectonics Research Center at AIST have newly designed and synthesized amphiphilic molecules with hydrophilic and hydrophobic moieties, and have developed a technique for the synthesis of various organic nanotubes of 40-200 nm in inner diameter, 70-500 nm in outer diameter, and several ┬Ám in length by self-assembling them in organic solvents.
This method needs less than one thousandth of the solvent used by conventional methods, enabling mass-production of organic nanotubes. Unlike carbon nanotubes, organic nanotubes have excellent dispersibility in water, and can incorporate guest substances of over 10 nm in size, such as proteins and nucleic acids. The organic nanotubes can encapsulate even functional substances that are so large that cyclodextrins, produced on a commercial basis as encapsulation substances at present, cannot do. Thus the organic nanotubes are promising for application to various fields such as medical, health, and nanobio technologies.
Source: AIST