Prototypes of plasma medical devices hold promise for their ability to quickly kill pathogens and cancer cells. But they are stationary, need external power sources to generate the power necessary for their electrical discharges, or need an external gas supply.
But as Jon Cartwright reports in Science, a flashlight-sized plasma device could greatly expand the innovation’s uses: to emergency calls, responses to natural disasters, and in military operations. Making the device portable is a big advance, says Michael Keidar, a plasma physicist at George Washington University in Washington, D.C.
“Operating cold plasma in air is challenging, [and] it seems like they were able to make it work,” he says. “This is a purely technical issue that was solved.”
Plasma devices are undergoing clinical testing to make sure they are safe to use but so far plasma — considered the fourth state of matter, or electrically charged ionized gas — has been shown to heal wounds and kill germs. Scientists believe that the plasma generates reactive oxygen that is highly effective against pathogens.
To test the device, reports Alexandra Sifferlin in TIME, Chinese and Australian researchers created thick biofilms of Enterococcus faecalis, a bacteria that frequently infects root canals and is known to be highly antibiotic- and heat-resistant. The scientists exposed the biofilm to the plasma flashlight for five minutes, and the treatment killed the bacteria, down to the deepest level.
“In this study we chose an extreme example to demonstrate that the plasma flashlight can be very effective even at room temperature. For individual bacteria, the inactivation time could be just tens of seconds,” says co-author Kostya Ostrikov, a professor at the University of Sydney, Australia, in a statement.
When applied to wounds, the plasma from the flashlight would produce reactive and long-living particles that interact with damaged cells and kill them, Ostrikov adds. The device could also be used in places where clean water and medications are scarce, reports the NY Daily News.
The portable device still has to go through clinical testing. But Ostrikov says that the plasma flashlight is “pretty much” a commercial device already. With technical modifications and economies of scale, the device could be priced at less than $100.
Source: “Plasma Flashlight Zaps Bacteria,” Science, 4/4/12
Source: “Bacteria-Bashing ‘Flashlight’ Could Help Save Lives,” TIME, 4/6/12
Source: “Hand-held ‘Flashlight’ That Zaps Germs Could Play Huge Role in Battling Infection Risks in Wars or Disaster Zone,” NY Daily News, 4/6/12
Image by Diliff, used under its Creative Commons license.
Dale McGeehon has been a journalist and editor for more than 25 years, covering chemical regulation and testing for Pesticides and Toxic Chemical News and innovations in material sciences for the National Technology Transfer Center. His writing credits include Omni and College Park magazines and The New York Times.