COPENHAGEN -- Here's the ultimate PDA accessory: a $50 module that analyzes a sample of your blood for anthrax and gives you the results on your Palm screen 10 minutes later.
A Danish nanotechnology research spinoff called Cantion is working on a technology it hopes will do exactly that. Other modules could check your blood for everything from AIDS to cancer.
The modules rely on biochips, slivers of silicon or other materials etched with microscopic channels that can be used to perform biochemical tests that now require a research laboratory.
"Commercial labs are probably going to hate us," said CEO Carsten Faltum, whose company is situated next to Denmark's National Micro and Nanotechnology Center on the outskirts of Copenhagen. "Doctors will be able to do all these tests themselves."
Doctors currently send most tests to laboratories, which charge premium prices and often take days for results. Doctors would welcome the extra income that doing tests on-site would generate, Faltum said.
Cantion is not the only company to develop biochips for medical diagnostics and research. Agilent Technologies, a Hewlett-Packard spinoff in Palo Alto, Calif., already has its own "labs-on-a-chip" on the market for analyzing DNA, RNA and other proteins. Motorola is also developing diagnostic biochips, and Thorion Diagnostics, another Danish nanotechnology spinoff located next door to Cantion, is developing a biochip device for doctors' offices which will cost around $5,000.
At as little as $50 a chip, Cantion is striving to be the low-cost leader (its microfabricated chips are designed to be thrown away after each use). By designing the modules to link to a doctor's PDA or computer, the company saves further on expensive instrumentation.
Abbott Laboratories and American Home Products are testing Cantion chips for developing diagnostic assays, and Faltum predicts that human clinical trials will begin within two years. Because the chips are diagnostic, FDA review would be quicker than for a drug.
Cantion's chips are distinguished by tiny cantilevers, microscopic diving board-like constructions feeding into equally small channels etched into the chips. "Catcher molecules" of DNA or other proteins designed to bind with, say, anthrax bacteria, are placed on the cantilevers.
A blood sample flows through the channels. If anthrax bacteria are present, molecules of bacteria will bind to the catcher molecules, causing the cantilevers to bend. That bending can be detected by measuring changes in electrical resistance.
Most other biochip diagnostic approaches rely on lasers, rather than electrical properties, to analyze biochemical assays. Lasers can change the nature of the delicate proteins streaming through the chip, and are more expensive, Faltum said.
Faltum predicts that biochips will also be used to test which drug therapies interact best with a patient's protein samples. "Look at Prozac," he said. "It only works in 33 to 35 percent of patients. If we had a test that shows it works on me but not on you, we'd save a lot of time, money and frustration."
