Implantable Chip

Years from now, a typical doctor visit might not include dull magazines, pharmacy lines, and saying "Ahh." Instead, a chip implanted in the body will function as a constant on-board doctor, detecting diseases early and delivering drugs straight into the bloodstream. Sound like an Orwellian/Asimov hybrid to be seen in an episode of a Jetsonic future space-age cartoon? Think again. Biosensors could make this scenario a reality before your toddler goes to college.

Biosensors are already thriving in the medical field. External biosensors are used in emergency rooms as point-of-care diagnostic units—such as i-Stat's "lab on a chip," which can reveal almost immediately whether a patient is in cardiac arrest by testing blood chemistry.

Other companies are developing implantable biosensors that track blood glucose levels and deliver insulin. MicroChips is testing a chip implant that offers long-term, time-controlled drug delivery. Digital Angel has discussed merging its external biosensors with the VeriChip, an implantable microprocessor.

If this decade's hurtling pace of biosensor advance continues, MicroChips president John Santini expects the technology to be used as in-the-flesh physicians within ten years. "It's a very exciting time," he says. "Our next step is a manually, wirelessly controlled biosensor that detects and treats an acute condition, and then a biosensor that will approximate an artificial organ; it'll sense a condition and respond automatically without user intervention."

Given the current zeitgeist, the market thrust has shifted to biosensors' security capabilities amid the hot topic of biowarfare. A recent report from market research firm In-Stat revealed that the media spotlight on this application may be premature: Despite the public's anticipation that biosensors with real-time detection will be able to monitor biological and chemical weapons, the technology hasn't caught up with expectations. Presently, biosensors in environmental monitoring stations nationwide can detect compounds like anthrax—but detection can take 12 to 24 hours. The best ones on the market take 20 minutes.

Sandia National Laboratories is developing the MicroChemLab, a system that detects biotoxins in 5 minutes. It should be deployed in the Boston subway within the next year, says microfluidics technical manager Art Pontau. His team is currently trying to upgrade the MicroChemLab to integrate both gas-based and liquid-based analysis into one handheld device.

This type of biosensor could be incorporated into military uniforms and eventually into houses as the biowarfare equivalent of a smoke detector, says Marlene Bourne, a senior analyst with In-Stat. At the current rate of technological progress, this real-time application could be ready within five years, though the social issues involved could lengthen the process. "It's a great application in theory, but if there's a false positive, panic could ensue—and a false negative could be a huge liability," says Bourne.

Meanwhile, experts disagree on how the focus on terrorism will affect biosensor development. Bourne says there's a concern that nonbiowarfare applications could get lost in the shuffle. One of the most important applications is in industry, where biosensors monitor air quality and emissions at chemical refineries and quality control at food-processing plants. Currently, testers take random samples off the food line and use biosensors to detect E. coli and salmonella. If funding isn't diverted to military applications, within five to ten years biosensors could be used in food lines to test every product.

Although national security presently drives the market, Pontau expects the MicroChemLab's ultimate goal to be a lab on a chip that immediately detects illnesses from cancer to the common cold. Indeed, some experts are banking on the defense industry to advance biosensor progress across the board. "If the defense arena can accelerate the program," says MicroChips' Santini, "I'm confident we'll have the biosensor artificial-organ system soon."