Developments to Watch
NANO-NEEDLES TO TAILOR MOLECULES
IMAGINE DIPPING AN ULTRAFINE QUILL PEN INTO PLATINUM ink, then using it to transform the chemical structure of individual molecules. In essence, that is what chemists at Lawrence Berkeley Laboratory Materials Sciences Div. have just done. Their feat signals the dawn of "nanocatalysis"--a technology that could allow chemical reactions to be triggered molecule by molecule.
Until now, most research in nanotechnology has centered on tracing the atomic surface of materials, using a new breed of microscope with a supersharp needle that can pick up the contours of atoms like a phonograph's stylus following the grooves in a record. The instrument used by the Lawrence Berkeley scientists is called an atomic-force microscope. It's like other such microscopes, except for one thing: Its point is coated with platinum, a common catalytic agent.
When the researchers touched the needle to an azide molecule, the platinum catalyzed a reaction, turning the azide into an amine molecule. Says Peter Schultz, the senior staff chemist who's leading the research: "Now we can do chemistry on surfaces instead of just looking at them." Developing nanochemistry to work with other catalysts and molecules, says Schultz, could point the way to custom-made materials with unique industrial applications, including new semiconductor materials. EDITED BY OTIS PORT