Lasers drive tiny toolset

Researchers from Nagoya University in Japan have used light to drive a pair of resin nano tweezers and a nano needle.

The scientists used photocurable resin and a laser beam to fashion a pair of tweezers and a needle whose tips measured 250 nanometers in diameter. A red blood cell is 5,000 nanometers across.

The researchers closed the tweezers and manipulated the needle while the tiny tools were immersed in liquid. The tiny tools could eventually be used to perform surgery on individual living cells, and manipulate individual molecules.

To work the tweezers, the researchers focused a laser beam on one arm to trap it, then swung the laser beam in an arc; the beam of photons, like wind on a windmill, pushed the tweezer arm, closing it against the other tip. The researchers were able to pivot the needle around a central point as fast as 34 times per minute using a similar method.

The method could be applied practically within five years, according to the researchers. The work appeared in the January 6, 2003 issue of Applied Physics Letters. -TECHNOLOGY RESEARCH NEWS