Engineers creating tests for biowarfare threats such as anthrax wanted to put more data on sample collection containers than bar codes could provide. They turned to a technology long used in packaging and materials handling that's starting to gain acceptance in the medical and life sciences field-RFID (radio frequency identification).

"RFID has a lot of features that bar codes don't have," says Jim Whelan, president of Alexeter Technologies, a Wheeling, IL maker of systems that test for anthrax, ricin, and other hazardous materials. The company currently makes field units for emergency teams, but is developing a PDA-based unit designed for labs. In both markets, data management and traceability are key factors driving the need for RFID tags.

Foremost among RFID benefits over bar codes is memory capability, which lets engineers store data on a tag. Even the basic 128 bytes on chips made by Maxell Corp. of America are enough for the first members in the PDA line. Alexeter stores 14 parameters in about a third of the total memory, using just the write-only registers. "We don't want anyone to be able to write over data," Whelan says.

Another critical factor is small size.

The Maxell tags fit on the 1- x 3-inch disposable units used to collect suspicious powders. "We were able to put the tags on our existing cartridge without altering the molds, which was very important to us since re-tooling is very expensive," Whelan adds.

The RFID chip measures only 2.5 mm square including the antenna. Some chips require antennae that are nearly the size of a credit card, but Maxell's antenna is housed on the IC. "The antenna goes around 64 times. It's electro-formed on top of the silicon, not etched," says Rumi Kitatate, marketing manager for new product development at Maxell, headquartered in Fairlawn, NJ.

Maxell is also developing its own medical product-test tubes with embedded RFID tags. The tags make it simple to track each sample in a study. "There are 96 test tubes in a tray, they're very close together, and each needs to be read independently," Kitatate says.

By putting tags on the bottom of the tubes, a reader scans them when the rack is placed atop the reader. Kitatate notes that the readers are much less expensive than those for 2D bar codes now used for this type of task. "Those readers cost $3,000 to $5,000. Ours will be about half that," he says. The reader can be as small as a credit card and can attach to PCs using USB connections.

Chips will cost under $1 each, Kitatate adds. Even though the RFID tags will have a fair amount of memory, speed is well within most lab requirements. "It takes less than a second to read 128 bytes," he notes.

Elsewhere in the medical and life sciences market, researchers are exploring a number of programs that use RFID tags. For example, Intel Research Seattle in Washington is working on a program that puts tags on medical bottles and other items in homes of elderly and ailing people who want to live at home. The tags make it possible to determine whether medications are taken and other routine tasks are being performed, saving money by avoiding the cost of moving the person to a nursing home for monitoring.