Chemistry: What is a Lab on a Chip?

Microchips in computers and electronics have become common place in today's technology. A large calculator of twenty years ago is now just one small application in your cell phone. But miniature chemistry? A laboratory on a chip? Yes, this application does exist and we are only beginning to scratch the surface of how useful this technology can be.

Back as far as 1997 research was being performed at Purdue University, research by ORNL began even earlier than the studies at Purdue. Specialized instruments used in chemistry labs have been shrunk from one thousandth up to one millionth of their original size. The design allows scientists to place dozens of miniature laboratories on one single silicon chip. These chips can perform multiple complex analyses all at the same time. The chips also increase the efficiency and reduce the costs of medical and chemical analyses.

Chromatography is the test used to separate mixtures into pure components for analyzing tissue and blood samples. Labs on a chip can perform the same work while eliminating the moving parts used in larger chromatography testing. The miniature chips also need considerably less liquid to obtain test results. Standard chromatography will not be completely replaced by this as chromatography is also used to purify products. The miniature chips only use a minute amount of liquid and are not be geared for purifying larger amounts.

These miniature labs are also being used to measure the molecular weights of proteins. Test performed this way are completed more quickly than using former technologies. Some of this technology is being used in the drug manufacturing and development industry. Channels that are smaller than a human hair connect reservoirs on a glass plate. Enzymes and substrates are mixed by a pressure difference and react and fluoresce under a laser. By using the miniature lab, close to one million compounds can be screened while only using one microgram of an enzyme. The enzymes used in testing and development can be costly and reducing the amount needed for testing results in less overall research cost.

Microchips can also be used for drug delivery in respiratory treatment. These devices offer an alternative to nebulizers in the treatment of asthma and other lung diseases. Drugs can be delivered directly allowing more medication to reach its destination and reduce the chances of adverse reactions. In addition to use in the medical field work these chips are also be designed to detect and identify chemical warfare agents and explosives. One small device is able to identify hundreds of different liquids and gasses. The smaller testing devices are not only less costly but provide results more accurately and quickly than traditional testing.

The miniature laboratories are manufactured by etching on a silicon chip. With this micro fabrication technique different versions of testing applications can also be created with ease. Sandia National Lab, Caliper Technologies and Purdue University are only some of the research laboratories that are working on this technology.

　

References:
　

http://www.sandia.gov/LabNews/LN04-24-98/chip_story.html

http://www.eurekalert.org/features/doe/2001-06/drnl-loa061902.php

http://news.uns.purdue.edu/UNS/html4ever/1997/9706.Regnier.labchips.html

http://www.rsc.org/publishing/journals/LC/article.asp?doi=b903575c