|Tweezers hold the device used to test new microbattery component.|
The cause of everything from the common cold to AIDS, viruses have a deservedly dreadful reputation. But a research team at Massachusetts Institute of Technology (MIT; Cambridge, MA, USA) may have found the one viral strain to good use: The researchers genetically engineered the virus to coax it into attracting cobalt-oxide molecules, ultimately assembling a nanowire that can function as an anode in a battery half the size of a human cell. Harmless to humans, the M13 viral strain used for the procedure is only capable of attacking bacteria.
In the Proceedings of the National Academy of Sciences, the team described assembling and testing the anode and electrolyte for the battery. “To our knowledge, this is the first instance in which microcontact printing has been used to fabricate and position microbattery electrodes and the first use of virus-based assembly in such a process,” explain MIT professors Paula T. Hammond, Angela M. Belcher, and Yet-Ming Chiang in that publication.
The researchers will next focus their attention on developing a microscopic cathode for the battery—again recruiting viruses to create an assembly line. “Once we’ve altered the genes of the virus to grow the electrode material, we can easily clone millions of identical copies of the virus to use in assembling our batteries,” says MIT professor Angela Belcher. The researchers anticipate that batteries built using the technology could be used for applications ranging from lab-on-a-chip devices to implantable medical sensors. Belcher says that a battery built using the technique would be biocompatible and the research group is interested in integrating such batteries with biological cells. In addition, the batteries could be stamped onto most conducting surfaces.
|An array of microbattery electrodes, each only about four micrometers in diameter.|
|Photos courtesy of Belcher Laboratory, MIT|