Nanoparticles allow fabrics to respond to bacteria, temperature, and radiation
September 17, 2010
By Jing Jin
On Sept. 14, the Wildfire Lounge in Ithaca Commons hosted this year’s first Science Cabaret, a monthly series of informal science lectures. Prof. Juan Hinestroza, fiber science and apparel design, gave a presentation on the use of biochemistry to fashion articles of nanoparticle-treated clothing.
Hinestroza hatched the idea of textile nanotechnology while reading about the 50-year cycles of technological advancements: textiles, railroads, cars, computers, and most recently, nanotechnology. The prospect of merging two revolutions separated by 200 years intrigued him.
What may have started as an experiment in novelty quickly proved to be an innovation with far-reaching health, military, commercial, and – of course – fashion applications. Hinestroza’s work shows the promise of a fabric that “will be able to sense and react” to its surroundings, killing bacteria, monitoring temperature and lessening the effects of UV radiation.
These effects are created through a selectively permeable layer of nanoparticles acting much like a cell membrane. Initially, the Hinestroza lab attached 300 layers of nanoparticles, each 20 nanometers thick, to the surface of cotton. This additional layer could not be perceived by sight or touch. Hinestroza was eventually able to lay down individual atoms and finally, nanoparticles of silver, gold, and platinum.
A critical property of the nanoparticle layer is the spacing between particles. Hinestroza conjectures that since the size of these spaces are comparable to that of bacteria cells, the spaces act like bacteria birth control, restricting the bacteria’s ability to reproduce. This potential germ-fighting power could be highly valuable to both the health care industry and consumers.
Hinestroza and his students are also exploring ways to incorporate drugs and cosmetics into the semi-permeable layer and release it in a controlled manner.
Varying the diameter of space between nanoparticles affects interactions of light and matter and can create illusions of color. Designer Olivia Ong ’07 used this concept to create a dress, colored not by dyes, but by nanotechnology.
This is the very process Hinestroza enjoys because he is able to “teach scientific concepts using the material everyone is familiar with.”
The military has taken an interest in utilizing this effect, not to produce colors, but to destroy them. Under infrared night vision, certain colors can be rendered invisible. At the moment, an invisibility cloak in the visible light spectrum is not yet possible due to movements in the fabric and the angle of the observer. Hinestroza is quick to add, though, that small patches a few millimeters wide have been made invisible, and further work on the bending of fabric is anticipated to produce further advancements.
As Hinestroza described innovation after innovation, the potential of nanotechnology textiles seems endless, especially because cotton is cultivated in 82 countries. After treatment with nanoparticles, the cotton remains 99.9 percent the same, yet something so commonplace has been made, “revolutionary by manipulating a few outer nanometers of material.”