Just in time for April Fools' day, a team has announced they’ve tested human blood, and it exhibits all the characteristics of the newcomer to the circuits family: the memristor.
Only it’s no April Fools' joke. S.P. Kosta of the Education Campus Changa in Gujarat, India and colleagues have published a paper in the International Journal of Medical Engineering and Informatics showing that human blood changes its electrical resistance depending on how much voltage is applied. It also seems to retain memory of this resistance for at least five minutes.
The team says that makes human blood a memristor: the fourth in the family of fundamental circuit elements that includes the resistor, the capacitor, and the inductor. Proposed in 1971, the memristor's existence wasn't proven until 2008, when HP senior fellow Stanley Williams and colleagues demonstrated a memristor device made of doped titanium dioxide.
Unlike other circuit components, the memristor has the ability to remember its previous state even when there's no current running across it. That property makes it a good candidate for memory devices that can be powered down without losing information.
This isn’t the first biological connection with memristors. Because the connections between neurons in the brain seem to exhibit some memristive behavior, memristors are considered a potential way to build devices that mimic neural systems.
Kosta and colleagues seem to have more therapeutic applications, like neuroprosthetics, in mind. “The study is exploratory in nature, but it opens up new vistas in treatment of human diseases by simple human body tissue-based electron circuit technology,” the team writes in the paper. According to the team’s press release, their next step will be to create small memristor devices that confine the blood to small channels. They'll try to combine them to carry out “logic functions”.
Rachel Courtland, an unabashed astronomy aficionado, is a former senior associate editor at Spectrum. She now works in the editorial department at Nature. At Spectrum, she wrote about a variety of engineering efforts, including the quest for energy-producing fusion at the National Ignition Facility and the hunt for dark matter using an ultraquiet radio receiver. In 2014, she received a Neal Award for her feature on shrinking transistors and how the semiconductor industry talks about the challenge.