Labs go portable with new miniature device

The Massachusetts Institute of Technology (MIT) has designed a portable "lab on a chip" diagnostic device, which the researchers say could identify biological or chemical weapons faster and easier than current methods.

The device has been specifically designed to perform hundreds of chemical experiments in any setting, but scientists think the technology can prove effective in a combat situation.

In the new system, known as a three-dimensional AC electro-osmotic pump, tiny electrodes with raised steps generate opposing slip velocities at different heights, which combine to push the fluid in one direction, like a conveyor belt.

Simulations predict a dramatic improvement in flow rate, by almost a factor of twenty, so that fast (mm/sec) flows, comparable to pressure-driven systems, can be attained with battery voltages.

Experiments in the lab of Todd Thorsen, assistant professor of mechanical engineering, have recently demonstrated the effectiveness of the design.

Thorsen's group is working toward integrating the pumps into a portable blood analysis device, which soldiers could carry onto the battlefield.

If exposure to chemical or biological weapons were suspected, the device could automatically and rapidly test a miniscule blood sample, rather than sending a large sample to a lab and waiting for the results.

"The chips are so small and cheap to make that they could be designed to be disposable," said Martin Bazant, associate professor of applied mathematics and leader of the research team.

Labs on a chip can also be used in traditional chemistry or biology labs to speed up processes such as DNA testing or screening for the presence of certain antigens.

Only tiny amounts of reactants would be needed, and experiments could be done more rapidly and efficiently.

"Instead of a thousand people pouring test tube A into test tube B in different laboratories, you've got a tiny little chip with thousands of experiments all going on at once," Bazant said.

Potential applications are not limited to military use - imagine going to a doctor's office and getting test results immediately.

The technology could also be useful for first responders. If emergency personnel knew immediately whether a person had suffered a heart attack or a stroke, they could start the appropriate treatment right away.