Technique controls nanoparticle size, creates large numbers

Pratim Biswas has a method that controls the size of the nanoparticles he makes, opening up possibilities for new nanotechnology applications and different techniques.

Biswas conducts research on nanoparticles, which are the building blocks for nanotechnology. For the first time, Biswas has shown that he can independently control the size of the nanoparticles that he makes while keeping their other properties the same. He's also shown with his technique that the nanoparticles can be made in large quantities in scalable systems, opening up the possibility for more applications and different techniques.

Nanotechnology has far-reaching applications in microelectronics, renewable energy and medicine, just to name a few. But the first step is synthesizing and understanding nanoparticles.

To put the size of a nanoparticle into perspective, compare it to a human hair. One strand of human hair is about 50 to 100 micrometers thick. One nanometer is 1/1000 of a micrometer. A nanoparticle is 100 nanometers thick.

"It's difficult to imagine dividing a meter up into a million pieces and then a nanometer is a thousandth of that," explained Biswas. "These are very tiny particles."

This small size is critical in the applications. By varying the size, nanoparticles can efficiently be tuned to perform a specific task, be it cosmetics or pollution clean up.

"When I reduce the size of the object, then the properties are very different. They can have certain unique properties," said Biswas. "By changing the size and the crystal structure you can tune the functionality." ...

•	Technique controls nanoparticle size, creates large numbers Scaling up the small business Nanotechnology Now online, Monday, Dec. 3, 2007 Byline: Contact: Tony Fitzpatrick, Washington University

	Story also ran in 2 others:  PhysOrg.com (VA) and Nanowerk LLC (HI)