Chemical Analysis Reduced to a Wee Chip
Lipkin, Richard, Science News
Imagine an entire chemical analysis system compressed onto a single chip--a little lab to carry anywhere, dip into samples, and give instant readings.
Sounds like a Lilliputian fantasy. Then again, maybe not.
D. Jed Harrison and colleagues at the University of Alberta in Edmonton, have built a bite-sized electrophoresis system, which separates compounds based on their densities and electrical charges.
Using ordinary microlithography techniques, the researchers etched capillary-sized channels onto a centimeter-long glass chip. With this tiny electrophoresis lab, the researchers could distinguish six fluorescently labeled amino acids in as little as 4 seconds, with a high rate of accuracy and efficiency. Their report appears in the Aug. 13 Science.
Based on this prototype, the team says, "It will be possible to develop a complete, miniaturized, integrated system with sample pretreatment, separation, and detection on a 'chip.'"
While their chip itself is not a complete lab, it is a major part of a lab. Down the road, complete chip-sized labs will make possible improved sensors, giving instant readings on a sample's changing chemistry, says chemist Zhonghui Fan, a coauthor of the report.
Scientists could, for instance, use a chip-lab to control quality during drug manufacture, to track an ongoing chemical reaction, or even to monitor blood chemistry inside a person's body. …