Digital Angel Developing an Implantable Glucose-Sensing RFID Tag

A team of RFID scientists, engineers and doctors is now working on the microchip. Their biggest challenge will be to develop a sensor tag able to function for up to six months after being implanted in the body. Because the body views microchips and other implants as foreign objects, scarring often occurs that can block the filaments' ability to work. Moreover, McGrath adds, the electrical currents the filaments rely on to measure glucose levels actually speed up the scarring process. "We've found a way to use far less current to stimulate the filaments, so fouling of the filaments doesn't occur as aggressively," he says. The glass casings on current implantable microchips protect them from any ill effects of scarring.

"There's still work that needs to be done to take the microchip from the design stage, and we are working with folks in the medical community to get the sensor tag to a stage where we think it will last and be reliable for six months." The goal, says McGrath, is for patients to swap out implants in alternating arms twice a year. In such a scenario, a doctor would remove the nonworking tag from one arm by making a small incision in the skin and insert a new tag via a procedure similar to giving a shot.

Digital Angel hopes to complete a prototype in a year, then begin clinical trials. Depending on the outcome of the trials, the company will apply for a license with the U.S. Federal Drug Administration some time after that date.

Once the product is ready to go to market, Digital Angel's sister company, VeriChip Corp., will market and distribute it. VeriChip, a subsidiary of Applied Digital, currently serves as Digital Angel's exclusive licensee in the area of human-implantable identification products. Digital Angel may also license the glucose-sensing microchip to other companies, McGrath says, such as drug and medical device distributors.

Work is underway to leverage RFID in other applications targeted at diabetics, as well. Cambridge Consultants, for instance, in collaboration with NXP Semiconductors (formerly Philips Semiconductors), reported in August that it had built an RFID-enabled prototype consisting of a glucometer and an insulin pump, designed to help diabetics better control the level of sugar in their blood (see Diabetic Device Uses RFID to Administer Insulin).