We hear the term nanotechnology on a regular basis in conjunction with reporting on new science and technology breakthroughs. But, what is nanotechnology? What sort of things is nanotechnology able to do right now and
what promise and peril might it hold for our future? Read on as we answer these questions in this week’s SciTech Watch.
Nanotechnology deals with technologies that use or are
involved with the very small. The prefix nano refers to 1 part in a billion. So when we say nanotechnology works on very small things we are speaking about things ranging in size from 1 to 100 billionths of a meter or 1 to 100 nanometers. Examples of items in this size range include the internal structures on computer chips whose size can in range of thousands of nanometers, to virus particles whose size range from 10 to 50 nanometers.
So what nanotechnologies are actually responsible for these advances? Most
have been achieved using nano-meter sized particles of various materials. Perhaps the most revolutionary of these are the family of molecules called fullerenes, they are also known as buckyballs, buckytubes, or nanotubes. Originally discovered in “ball” form, a fullerene buckyball (The term bucky comes from the shortened forename of
Buckminster Fuller whose geodesic domes used the same shaped supporting structures as buckyballs have) is composed of 60 carbon atoms bonded together to form a ball-shaped particle. When additional carbon atoms are added to the structure, the ball elongates into a tube, hence the name buckytube or nanotube. Although nanotubes have been shown to possess or create many enhancements to existing materials, the widespread use of nanotubes is limited by our current inability to produce them in large quantities and defined lengths.
Here are just a few of nanotubes’ potential uses: enhanced material strength, nanotubes have one of the highest tensile strengths ever measured. Adding them to materials we use to build things should increase their strength while not appreciably adding to their weight. The side steps of some SUVs and vans are made from plastics blended with tiny nano-sized fibers of carbon. These plastic composites are superior in strength and durability while weighing and costing less. Fabrics are being produced with coatings of nano-sized whiskers. These whiskers interfere with a stain’s ability to wet the treated fabric, thus rendering the fabric stain resistant.
In television displays, nanotubes can function as electron emitters and a 14-inch monochrome television has been built using them to power the display. The Organic Light Emitting Diode (OLED) powered displays will be larger and less expensive than current flat-panel TVs can produce. Chemical sponges, nanotubes act as chemical sponges capturing small gas molecules inside their tubular walls. Nanotubes may be used to filter contaminants from the air and other gases, and deliver drugs in more precise fashion.
Like all technology, nanotechnology has its dark side . Research is beginning to show environmental and health issues that may be related to nano-sized particles. Due to their very small size, nano-particles could cross the blood-brain barrier and cause brain damage. Research presented at the 2005 meeting of the Society of Toxicologists indicates that inhaled nanotube particles can travel to the deepest recesses of the lungs where the body’s efforts to fight them result in lung inflammation, scarring and creation of granulomas where the nanotubes are entombed.
Many researchers who acknowledge the potential dangers of nanoparticles point out, however, that industry safely uses countless toxic and dangerous substances. With proper precautions and design, nanotechnology holds significant promise to provide us with innovative new products in a wide variety of areas.