A Sharper Nose for Danger
Research into biodetectors to sniff out potentially deadly pathogens has gone on for years. Even so, the devices the Homeland Security Dept. uses in BioWatch, its network of biosensors that analyze air in more than 30 major U.S. cities, are only a tad smarter than a vacuum cleaner. Basically, they just suck in air and deposit the samples onto special filters. Then someone has to collect the samples and take them into a lab.
It's all pretty Old Tech -- and expensive. Today the network costs about $2 million per city, per year, says Penrose "Parney" Albright, Assistant Secretary for science and technology at Homeland Security. That's mostly due to the labor involved.
But Albright figures these expenses will fall by half when, in late 2004, the department introduces a new breed of biodetectors that not only collect samples but also conduct tests right on location -- and send the results to the lab wirelessly.
Indeed, in the nearly three years since September 11, biodetectors have come a long way. Made by a host of companies, from chipmaker Texas Instruments (TXN ) to hundreds of startups, these tiny devices are designed to react in a certain way when they come in contact with a specific agent, such as anthrax. Equipment attached to a sensor, which can be as small as a speck of dust, detects fluorescence or other indicators that set off danger signals.
The newest generation of biosensors is smaller, reusable, and capable of testing far more agents. That's driving down the cost of building and operating sensor networks. And that's why, starting in October, 2005, Homeland Security plans to test the biodetectors not only outdoors but in buildings, says Albright.
Such additional uses will certainly boost to sales. With biodetection devices becoming smaller and cheaper every year, demand is expected to rise from $7.3 billion in 2003 to $10.8 billion in 2007, according to Kiji-Keizai USA, a high-tech consultancy based in New York.
Sales also are being fueled by new communications capabilities that are being embedded in the tiny devices. Consider this: Four months ago, Starkville (Miss.)-based Global Technology Resources/Datastar launched thumb-size sensors integrated with RFID (radio-frequency identification) tags. When attached to containers with food, these sensors continuously test for diseases or abnormal concentrations of bacteria and alert suppliers and retailers of any tampering en route via satellites, says Paul Cheek, the company's president.
TRAPPED FOR TESTING.
It also helps that the newfangled sensors can sniff for biological and chemical agents at the same time. Frances Ligler, senior scientist at the Naval Research Laboratory in the Center for Bio/Molecular Science & Engineering in Washington, D.C., has developed a shoebox-size detector that could potentially test for more than 100 different toxins, bacteria, and viruses at the same time -- today's sensors can only handle up to eight. The lab is now in talks with several companies to have the detector commercialized, says Ligler.
Ligler's device has several other nifty qualities: For one thing, it doesn't kill the bacteria but simply binds to them, says Daniel Lim, a microbiologist at the University of South Florida in Tampa who worked on the sensor. As a result, the trapped bacteria can later be used for further testing, such as checking their resistance to antibiotics. It's also one of the industry's first reusable sensors, which could be a big cost saver.
Costs, as well as size, are key to widescale deployment -- and here too, the latest manufacturing technology can help. Scientists at the University of California, Riverside, design their sensors with wires much smaller than the diameter of a human hair in width and made of superconductive polymers. A special enzyme trapped inside the wire can bind to a deadly chemical agent, like that found in nerve gas. A change in the wire's connectivity indicates a positive result, explains Ashok Mulchandani, chairman of chemical engineering at UCR.
A Boston-area startup takes an altogether different tack. SRU Biosystems, chaired by Gordon Binder, former CEO of biotech giant Amgen (AMGN ), is developing its own reusable sensors. But its device looks like a videocassette. Agents are bound on the tape's surface, then, after the testing, the tape can be rewound for reuse, says Brian Cunningham, SRU's founder and CTO. The presence of agents on the tape is confirmed by shining low-power light onto the film. SRU is now testing the sensors in drugmaking, but it's also hoping to develop models for sniffing out biological agents within buildings.
Indeed, many of the new sensors will find uses outside of homeland security -- say, in testing human blood for diseases or milk for E. coli. "In the U.S., a lot of people say, 'We're putting so much money into homeland security,'" Lim says. "But much of what's being done here can have applications in other areas. So this is money well spent." And as biosensors leave their Stone Age, they're proving to be a vital tool for dangerous times.
By Olga Kharif in Portland, Ore.