A new type of microchip that moves and isolates DNA and protein molecules could be used to identify medical problems or detect viruses and other biohazards before they spread.
"The biosensor chip has tiny wires, about onefifth the diameter of a human hair, embedded in a circular pattern," says Eric Simone, a senior biomedical engineering student at Johns Hopkins University. "When it's connected to a power source, it lets us generate an electric field that can transport molecules to a designed area," he adds.
The chip takes advantage of the natural negative charge possessed by DNA or of a surface charge imposed on the molecules. A tiny drop of liquid containing the DNA is placed on top of the chip. The electric field guides the molecules to a designated area, where they can be analyzed under a microscope.