A U.S. soldier is on patrol with his squad when he kneels to check something out, unknowingly putting his knee into a puddle of contaminants.
The soldier isn't harmed, though, because he or she is wearing a smart suit that immediately senses the threat and transforms the material covering his knee into a protective state that repels the potential deadly bacteria.
Scientists at the Lawrence Livermore National Laboratory, a federal government research facility in Livermore, Calif., are using nanotechnology to create clothing designed to protect U.S. soldiers from chemical and biological attacks.
The researchers turned to nanotechnology to overcome the tough task of creating military-grade protective clothing that's breathable and isn't heavy to wear.
"The threat is nanoscale so we need to work in the nano realm, which helps to keep it light and breathable," said Francesco Fornasiero, a staff scientist at the lab. "If you have a nano-size threat, you need a nano-sized defense."
For a little more than a year, the team of scientists has focused on developing a proof of concept suit that's both tough and inexpensive to manufacture. The lab group is teaming up with scientists from MIT, Rutgers University, the University of Massachusetts at Amherst and other schools to get it done.
Fornasiero said the task is a difficult one, and the suits may not be ready for the field for another 10 to 20 years.
Ross Kozarsky, a senior analyst with Boston-based Lux Research, said the effort could also lead to a lot of other uses for smart nano-based clothing or devices.
"I think it's definitely innovative. It's a pretty powerful platform technology," he added. "Materials that intelligently react to their external surroundings -- that is certainly an interesting class of materials. This is at the front end of the tunnel. Imagine an athlete wearing some kind of clothing that reacts to humidity or temperature and can make itself a lighter or warmer shirt."
Kozarsky also noted that smart clothing could be used for personal tasks, like measuring a user's heart beat, pulse and blood pressure.
The technology could also lead to smart footwear, which could, for example, transform itself to repel potential danger found in water and keeping the user's feet dry.
The military also might consider adapting the base technology so instead of a nano-infused fabric transforming itself to protect a human from a biological or chemical attack, the smart material could be body armor that automatically strengthens itself based on the stress it's under.
"This is a big step forward for nanotech," said Ming Su, an associate professor of biomedical engineering at Worcester Polytechnic Institute. "It can lead to a big area of bionics. Basically, you are dealing with man-made stuff that ... can achieve certain biological functions -- having a self-sensing ability or self-healing abilities, or localized protection from toxic materials."
Think, he added, of a baby blanket or baby clothes that could become warmer when the temperature drops. The same technology could be used to make gloves that can detect high heat or hazmat suits that become more protective when they detect toxins.
"This is very good work, definitely," said Su. "I would say it will have a large impact."
Building better protection
The U.S. military today does have protective gear for soldiers who are under threat of biological or chemical attacks, but it's big, bulky, heavy and hot to wear.
Today's suits can only be worn for an hour or two at a time, according to Fornasiero. "Your physical abilities drop and you can get heat stroke [wearing them]," he said. "It's a big problem."
The Lawrence Livermore team isn't taking just one track to make that happen. They're working on at least two different options for the carbon nanotubes.
One option is to use carbon nanotubes in a layer of the suit's fabric. Sweat and air would be able to easily move through the nanotubes. However, the diameter of the nanotubes is smaller than the diameter of bacteria and viruses. That means they would not be able to pass through the tubes and reach the person wearing the suit.
However, chemicals that might be used in a chemical attack are small enough to fit through the nanotubes. To block them, researchers are adding a layer of polymer threads that extend up from the top of the nanotubes, like stalks of grass coming up from the ground.
The threads are designed to recognize the presence of chemical agents. When that happens, they swell and collapse on top of the nanotubes, blocking anything from entering them.
A second option that the Lawrence Livermore scientists are working on involves similar carbon nanotubes but with catalytic components in a polymer mesh that sits on top of the nanotubes. The components would destroy any chemical agents they come in contact with. After the chemicals are destroyed, they are shed off, enabling the suit to handle multiple attacks.
"We are not selecting either option," said Fornasiero. "We have multiple options and we don't know what will work so we will keep looking."