Nano test tubes fabricated

Researchers from the University of Florida have found a way to make minuscule test tubes from carbon and silica nanotubes. Nanotubes are rolled-up sheets of atoms that can measure less than 1 nanometer in diameter, and carbon nanotubes occur naturally in soot. A nanometer is the span of 10 hydrogen atoms.

The nano test tubes could eventually be used -- along with tiny caps -- to bottle small numbers of molecules such as drugs, DNA, or proteins and release them in specific places in the human body.

The researchers made the nano test tubes by modifying their template method of making open-ended nanotubes.

The researchers grow nanotubes in a membrane-like alumina template. The diameter of the test tubes depends on the diameter of pores in the template and the length of the test tubes is determined by the thickness of the template. They were able to make nano tubes that were closed on only one end by adjusting the template so that the pores were closed on one end.

The method can be used to make nanotubes from many different materials, according to the researchers. This opens the possibility of creating tubes with different biochemical properties. The researchers are also able to modify the outer surfaces of the test tubes to, for example, encourage their uptake by particular types of cells.

Nano test tubes could be used practically in 10 to 20 years, according to the researchers. The work appeared in the March 10, 2004 issue of Nano Letters.