Imagine an army of spies so tiny it could go almost anywhere undetected. The U.S. Department of Defense already has. For years their technology development arm, DARPA, has been working to create insects that will move where they’re directed. But forcing insects to go where you want them to is just half the battle. To outfit them with electronic devices—like miniature video cameras or sensors to detect poison gas, for example—you need a lightweight power source.
Last week, a team of researchers led by chemist Evgeny Katz of Clarkson University reported that they had successfully implanted biofuel cells into brown garden snails. To extract energy, the team poked electrodes through the snail’s shell into the blood-like liquid called hemolymph that lies below. The enzyme-coated electrodes harvest energy from glucose and oxygen in the hemolymph.
The snails couldn’t generate much energy, about 0.5 Volts. But Katz says the electrical energy could be stored in a condenser and then released to power an external device. In fact, that work is already underway in his lab. The next step, Katz says, is to create an organism that can power an attached micr0-sensor capable of monitoring the environment. Slow-moving snails aren’t exactly the ideal soldier, but Katz and his colleagues are also studying other organisms that might be better suited to military applications.
Other groups are working on implantable biofuel cells as well. Earlier this year, researchers successfully implanted biofuel cells in the abdomens of cockroaches, which move at a much quicker clip. And, according to Nature news, another research group accomplished the same feat in beetles.
Fuel cells aren’t the only way to get energy from small organisms. Scientists are also using piezoelectric materials, which generate current when deformed, to convert the mechanical motion of bugs’ wing beats into electricity. And in 2009, a team of scientists developed a moth fitted with a transmitter powered by radioactive isotopes. Moths have been a favorite with the Department of Defense. According to the Washington Post, in 2007 DARPA program manager Amit Lal talked about Gandalf using a moth to call for air support when he was trapped in The Lord of the Rings. “This science fiction vision is within the realm of reality,” he noted.
Last year, a team of researchers reported that they could steer a moth’s flight by attaching a neural probe to the insect’s ventral nerve cord. Check out this video of the moth in flight. Combine that technology with the power-producing biofuel cells, and the reality Lal envisions may not be so far off.
I have glimpsed the future. And it is teeming with creepy crawly cyborgs. Shudder.