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Battery-Powered Plasma Flashlight Makes Short Work of Bacteria
cylonlover writes "An international team of scientists has created a handheld, battery powered device that has been shown to effectively rid skin of bacteria in an instant by blasting it with plasma. The plasma flashlight, which shouldn't be confused with a plasma torch that will damage much more than bacteria if used on the skin, could provide a convenient way for paramedics and military personnel to deal with harmful bacteria in the field. The self-contained device is powered by a 12 V battery and doesn't require any external gas feed or handling system. The plume of plasma it generates is between 20-23C (68-73.4F), so it won't damage the skin. It is also fitted with resistors to stop it heating up and becoming too hot to touch. Its creators say it can also be easily manufactured at a cost of less than US$100 per unit."
I like the bacteria that live on my body.. we have a relationship, once in a while a renegade causes some mayhem but otherwise its a very healthy existance that we've agreed to. Keep your death lights away, I dont need them.
"It is also fitted with resistors to stop it heating up and becoming too hot to touch."
Um. What? Whoever wrote this clearly has no electronics knowledge. This is Slashdot. We have real engineers and scientists around here. Could we have real science reporting, please? Not only is that sentence moronic, the entire article fails to explain how this device operates, even in the most basic terms. It's shaped like a flashlight, but that seems to be where the similarity ends. It is not a light source whatsoever. From the actual scientific publication, it appears that this is a high voltage pulse generator that produces a discharge between the device and the patient. A series of 100ns pulses at 20KHz repetition rate ionizes the air between the device and the patient, thus producing the ions that kill the bacteria. The peak current is 6mA, but the average current (and thus average power) is very low so heating is minimal. This is a relatively low-tech device electronically, and could easily be replicated by many hobbyists.
I am a geek attorney, but not your geek attorney unless you've already retained me. This is not legal advice.
There's a paywall? Didn't notice, but here you go:
Battery-powered plasma flashlight makes short work of bacteria
By Darren Quick
00:51 April 5, 2012
An international team of scientists has created a handheld, battery powered device that has been shown to effectively rid skin of bacteria in an instant by blasting it with plasma. The plasma flashlight, which shouldn’t be confused with a plasma torch that will damage much more than bacteria if used on the skin, could provide a convenient way for paramedics and military personnel to deal with harmful bacteria in the field.
The self-contained device is powered by a 12 V battery and doesn’t require any external gas feed or handling system. The plume of plasma it generates is between 20-23C (68-73.4F), so it won’t damage the skin. It is also fitted with resistors to stop it heating up and becoming too hot to touch. Its creators say it can also be easily manufactured at a cost of less than US$100 per unit.
In an experiment carried out by the scientists, the plasma flashlight effectively inactivated thick biofilms of Enterococcus faecalis, a bacterium that often infects the root canals in dental treatments and is highly antibiotic- and heat-resistant. Created by incubating the bacteria for seven days, the biofilms consisted of 17 different layers of bacteria. After treating each biofilm with the plasma flashlight for five minutes, the plasma was found to penetrate deep into the very bottom layer and inactivate the bacteria.
“In this study we chose an extreme example to demonstrate that the plasma flashlight can be very effective even at room temperature,” said co-author of the study, Professor Kostya (Ken) Ostrikov, from the Plasma Nanoscience Centre Australia, CSIRO Materials Science and Engineering. “For individual bacteria, the inactivation time could be just tens of seconds.”
While plasma has previously been shown to effectively kill bacteria and viruses on the surface of the skin and water, the exact mechanism behind this is still not understood. Ultraviolet radiation has been theorized as a reason, but the jet created by the plasma flashlight is low in UV radiation, which adds to the safety of using the device on a person’s skin. The reactions between the plasma and the surrounding air has also been suggested as another possibility.
The international team behind the plasma flashlight consists of scientists from Huazhong University of Science and Technology, CSIRO Materials Science and Engineering, The University of Sydney and the City University of Hong Kong. Their work is detailed in the Journal of Physics D: Applied Physics.
Source: Institute of Physics
MRSA is a direct product of our total war on all bacteria. Most people who become infected with MRSA were exposed to it in a hospital. Hospitals have basically become ultra-efficient incubators for MRSA.
Wonder if it works on solid surfaces as well. Just imagine, use it on your face a few times a day and eliminate acne. Of course you'll probably get really tan really quickly, but yeah. No more Yellowish Brown splotches as you leave after donating blood, they can sanitize you with a quick brush of a plasma flashlight. If places replaced the costly paper towel dispensers and soap dispensers with one of these, (a heavy duty plugin version) you could sanitize the hands of a hundred people in like a minute! No more soap and wasteful paper towels that are almost never recycled after use as a hand towel. No more costly hot air hand dryers that take hundreds of watts to run.
Something fishy about this. "Fitted with resistors to stop it heating up". Is that a joke? As I remember, resistors are about turning unwanted current flow into heat. Also - from the article, the way I interpret it, it seems it takes tens of seconds of exposure to kill the bacteria.
Antibacterials like simple alcohols or hydrogen peroxide are small molecules, and small molecules can't generate an immune response directly. However, small molecules can act as haptens: They bind to some protein and the combination generates such a response. Urushiol is the best example of a hapten - it's the "active ingredient" in poison ivy, oak, and sumac.
That said, I've never heard of an allergic reaction to either a simple alcohol or hydrogen peroxide. Skin irritation, sure, but not an allergic reaction.
Iodine is another matter. Antibacterial iodine is usually povidone-iodine, and it definitely is possible to have a severe allergic reaction to it. Various sources disagree as to why this happens, but it definitely does.
It's also possible, although rare, to have an allergic reaction to iodine-based contrast dyes. My mother nearly died from an injection some of this stuff, as a matter of fact.
Yes, and it worries me to read "we don't know how it kills the bacteria" and "it's only 20-23C, so it won't damage the skin" in the same article. I'm not one of those "OMG it might cause cancer" types, but this seems to be one example where such fears could be warranted. After all, you could say "it's only 20-23C so it won't kill any bacteria" but that's obviously not true. Could we maybe first figure out what it does exactly before declaring it safe and letting paramedics use it on a daily basis?