Under
a powerful microscope it looks like an alien – something out of Roswell,
N.M., or “The X-Files.”
But a brand-new, tiny fiber dubbed the “alien nanofiber,” co-invented by a North
Carolina State University textiles professor and a chemical engineering professor
from the University of Puerto Rico, Mayaguez, has the potential to become a big
deterrent to counterfeiters.
NC State's Dr. Juan Hinestroza, assistant professor of textile engineering, chemistry
and science, and Dr. Carlos Rinaldi, assistant professor of chemical engineering
at the University of Puerto Rico, Mayaguez, created novel nanoscale fibers that
can be placed inside a garment or paper document and serve as a “fingerprint” that
proves the garment or document is genuine. Graduate student Carola Barrera and
high school student Aldo Briano are also involved in the research.
At about 150 nanometers in diameter, the fibers
are smaller than living cells and invisible to the
naked eye. A nanometer is one-billionth of a meter;
for comparison purposes, the Web site for the National
Nanotechnology Initiative, a federal research and
development initiative that coordinates multiagency
efforts in nanoscale science, says that a human hair
is about 80,000 nanometers wide, while a sheet of
paper is about 100,000 nanometers wide.
The tiny fibers are designed to have within them
even smaller nanoparticles with an electrical, magnetic
or optical “signature” that can prove a product genuine.
The product would need only be scanned, or read, by a device looking for the
particular signature.
For example, Hinestroza says, name-brand clothing with nanofibers can be scanned
at different points in the supply chain to ensure pirated clothing doesn't get
into retail outlets or into your closet. Passports with nanofibers can be scanned
to ensure their legitimacy. Ostensibly, paper money with nanofibers would help
ensure fake twenties don't get into your wallet – or the grocer's till.
“The fibers can essentially serve as molecular bar codes,” Hinestroza says. “We
can control the position, frequency and distribution of particles inside the
fibers, and their signature.”
He also says that manufacturers wouldn't need to change the ways they make things
in order to include the nanofibers.
“These fibers can be easily incorporated into existing textile manufacturing
facilities,” Hinestroza said. “Textile products are the perfect vehicles for
incorporating nanotechnology into commercial applications.”
The process used to create the nanofibers is called electrospinning, a textiles
manufacturing process first used in the 1930s but now being put to use to create
tiny fibers.
In their electrospinning research, the scientists apply electrical charges
to water-based polymer solutions containing tiny nanoparticles, including magnetic
particles or quantum dots, tiny particles that, depending on their size, display
colors. When enough electrical charge is applied to the solution, an unstable
jet – or narrow stream of solution and nanoparticles – moving like a whip through
air, is formed. The whipping motion elongates the jet while the solvent evaporates,
producing a tiny fiber containing the nanoparticles.
The researchers then tested the fibers and found the fibers had magnetic properties.
Hinestroza and Rinaldi have been invited to present their nanofiber findings
at a number of academic conferences in the next few months.
The research is sponsored by a National Science Foundation Nanoscale Exploratory
Research grant, and by the NC State Nanotechnology Steering Committee.
Media Contact:
Dr. Juan Hinestroza
919/515-9426
Mick Kulikowski
News Services
919/515-3470
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