'Nanosprings' may help detect cancer

A tiny structure developed by scientists at Georgia Tech could be used to detect single molecules, or as a key component in nanodevices.

Scientists at the Georgia Institute of Technology have recently developed a tiny "nanospring" structure that could be used to detect individual molecules, possibly creating an extremely sensitive method of detecting cancer. The nanosprings could also be used to activate devices built on a molecular scale.

Georgia Tech's Center for Nanoscience and Nanotechnology said the nanosprings are smaller than any comparable structure, including the "nanobelts" developed by the institute in 2001.

Much research into the area of nanotechnology--or devices constructed on a molecular scale--has focused on creating smaller and more-efficient microchips. Nanosprings and nanobelts could make an impact on an area that includes devices such as sensors, which interact with forces and molecules in the surrounding environment.

Georgia Tech researchers Xiang Yang Kong and Zhong Lin Wang are currently developing the first application for the nanospring, a micron-size "pill" that would distribute millions of the nanosprings throughout the body.

When the structures encountered even a single cancer-protein molecule, they would send a radio signal through the skin, the researchers said. A prototype is planned by the end of the year, they said.

"We would like to use these materials for in-situ, real-time, nondestructive monitoring within the body with high levels of sensitivity," Wang said in a statement.

General Electric is working on similar technologies. The challenge right now isn't so much making molecules that will seek out infected or malignant cells, researchers at GE said. Instead, it's figuring out how to prevent them from clumping. Commercialization of such technologies, however, could take time because of health risks and regulatory concerns, several sources have said.

The zinc oxide-based nanosprings are 10 nanometers to 60 nanometers wide and five to 20 nanometers thick, but up to several millimeters long. One nanometer is one billionth of a meter.

The nanosprings are made useful by their piezoelectric and electrostatic polarization properties. Piezoelectric materials, which include quartz, Rochelle salt and various synthetic crystals, produce a voltage when a mechanical stress is applied, making them suitable for devices such as phonograph cartridges, microphones and strain gauges.

Nanomaterials with electrostatic polarization can be used to attract specific molecules, making them potentially usable as biosensors.

Matthew Broersma of ZDNet UK reported from London.