This summer, when you’re lounging poolside, you can slather your skin in sunscreen that blocks harmful rays without leaving a whitish film. Or if you’re viewing the water from your high-rise, beachfront hotel, you can look out a window kept clean with a thin coating.
These are just two breezy examples of nanotechnology’s growing ubiquity. Work on the nanoscale – that is, with components that could be smaller than a strand of DNA -- is also kicking into high gear across Pennsylvania.
, director of Drexel University's Nanotechnology Institute
, says the idea of building materials atom by atom in order to have specific properties has become commonplace over the past several years.
"Nanotechnology is almost everywhere now," says Gogotsi, co-founder of Bucks County-based Y-Carbon
. "Nanotechnology's not even a separate field of science. It's more of a philosophy."
"We're not looking for small steps," says Leoné Hermans-Blackburn, executive director of the commercialization center. "We're looking for significant, impactful technologies."
The same is true for the federal government, which offers funds for nanoscale investments through dozens of programs
. Sally Tinkle, interim director of the National Nanotechnology Coordination Office, says the federal government has shifted its focus from advancing the field in general to developing applications for it and transitioning them to the marketplace. Her office's focus lies in areas such as manufacturing and renewable energy.
Hermans-Blackburn notes that many of the nanotechnology developments taking place around the state are focused in areas including electronics, software, robotics and the life sciences. Industries in the state are looking beyond their own organizations and seeking to partner with researchers who can advance technologies.
Researchers across Pennsylvania are discovering new ways to apply nanotechnology. Here are three examples.
XiGo Nanotools: A Simple Measuring Device
Measuring something that can only be seen underneath a microscope isn't easy. Much of the machinery capable of measuring nanoparticles is difficult to use and requires separating the particles from any liquid they might be floating around in.
So in 2005, Sean Race and David Fairhurst started XiGo Nanotools
to develop a device that could measure the surface area of nanoparticles while they were still in liquid, which is how they are typically made. Their tool would be easy to use, even for technicians without a doctorate.
Race explains that figuring out a particle's size and surface area is one of the keys to developing nanomaterials with the properties that companies and researchers want. "Materials behave much differently on the nano scale than the macro scale," he says.
XiGo's been selling its device, the Acorn Area
, for about two years. It takes a tube with a sample of the particles being measured and measures their surface area in about a minute. Race says its most common buyers include companies that make electronics, specialty chemicals, medicine and inks. "Since there's nothing else like it out there, it's not hard to sell it," he says.
For example, Race says the most expensive part of most drugs is the active ingredient. If a pharmaceutical company can find a way to use less of an active ingredient, it can make the medicine less expensively.
About a year ago XiGo started selling a similar device called the Acorn Drop. It's designed for testing particles in emulsions, a category of liquid mixtures. Race says its biggest buyers are companies that make pharmaceuticals, food and personal-care products like makeup.
He'd like to see the Acorn Area and Acorn Drop in more industrial quality-control labs. He also sees potential for XiGo's technology to be used as a medical device that could produce results from blood samples in minutes instead of days. Another potential market is the energy industry, which could use it as part of the search for more efficient reusable batteries.
"Wouldn't it be great to be able to plug in your car for 10 minutes and be able to rock?" Race asks.
Sen Research Group: Motors on the Nanoscale
Without motors, your car wouldn't move and your electric toothbrush wouldn't live up to its name. Likewise, many nano-sized devices need some sort of motor if they're going to work.
Scientists like Ayusman Sen, a chemistry professor at Penn State, have spent years figuring out how to make nano-sized motors that could lead to devices with a wide range of functions. "We want to take objects that are that small and endow them with the ability to move and communicate with each other," says Sen, whose research group
gets funding from sources including the National Science Foundation
, and the Advanced Energy Consortium
The idea sounds simple. Nature offers myriad examples of organisms that use their instincts and work together to accomplish a goal. Even ants follow chemical trails leading them down the shortest route toward sources of food.
But when it comes to building motors, the nanoscale presents a few limitations. Unlike an electric toothbrush that's powered by a battery, nanomotors are too small to carry their own fuel. Objects that small are easily buffeted by air or liquid they float in, which makes it difficult to move them in a specific direction.
But over the last several years, Sen's research group has developed nanomotors
that are capable of performing specific tasks. Some lure particles toward them, like a hungry baseball fan toward the smell of a hot dog. Others draw particles toward them like a magnet before releasing them just as quickly.
"One bot can control the movement of all the other ones around it," Sen explains. "They know how to move on their own."
Commercial applications for this groundbreaking work are years away. But he says plenty of potential exists for what self-directed nanomotors can do.
Anytime a tiny motor like this can be anchored in one spot, Sen says it can function as a pump of some sort – perhaps an implantable, glucose-triggered insulin pump that could keep a diabetic's blood-sugar levels in check without forcing her to check her blood several times a day. Or a nanomotor could zero in on a hairline fracture in a bone and deposit the same minerals that bones are made of.
Beyond the human body, Sen says his group's work has garnered notice from oil companies. They would love to see nanomotors that can explore the cracks and crevices in a well and detect oil inaccessible with current drilling technology.
Y-Carbon: The Potential of Activated Carbon
The substance that plays a starring role inside a typical household water filter has the potential to alter how wounds are healed and how efficiently batteries operate.
, based in the Philadelphia suburb of Bristol, specializes in a material called activated carbon. You've seen it at work if you've ever filtered your water into a pitcher. Essentially, it's a porous form of coal that is useful for a wide range of chemical reactions.
The scientists at Y-Carbon process activated carbon – mostly from coal, wood and coconut shells -- with a hard material called silicon carbide. This gives the resulting nanoparticles different characteristics.
"We make a lot of different materials," CEO and co-founder Ranjan Dash says. "We can control the properties."
The clients that come to Y-Carbon come from a variety of sectors, from food processing to batteries, and they all need activated carbon with specialized properties.
For example, Dash says one product
that's used in the food industry can extend the shelf life of produce. It comes in sachets that can be packaged along with fruits and vegetables, absorbing a gas called ethylene that produce generates as it ripens. If the ethylene is absorbed, the fruit will ripen more slowly and stay fresh longer.
Another one of the company's product lines
comes in tablets that can absorb toxins from human blood. (Activated charcoal, another term for activated carbon, is actually one of the recommended antidotes for ingesting certain poisons.) Y-Carbon sees potential for this product to be incorporated into new techniques for treating wounds because of its ability to suck out toxins. Dash says his company is making this material available to other researchers who are interested in pursuing how it could be used to treat injuries.
These are just a few uses Y-Carbon has found for this humble substance, and they're just the beginning. The company is currently exploring other possible applications, such as water desalination. As Dash explains, activated carbon's ability to purify tap water could be put to work removing viruses, bacteria and salt from water. That technology is still being developed, but could go a long way toward preventing devastating water-borne illnesses in developing nations.
REBECCA VANDERMEULEN is a freelance writer who lives near Downingtown. As she tells friends out of state, that's between the cheesesteaks and the Amish. Send feedback here.
PHOTOS of XIGO Nanotools president Sean Race and the Acorn Area by JASON FARMER