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Battery-Powered Plasma Flashlight Makes Short Work of Bacteria 133

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."
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Battery-Powered Plasma Flashlight Makes Short Work of Bacteria

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  • No thanks. (Score:3, Insightful)

    by Adult film producer ( 866485 ) <> on Thursday April 05, 2012 @11:04PM (#39594125)
    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.
    • by toygeek ( 473120 ) on Thursday April 05, 2012 @11:06PM (#39594141) Homepage Journal

      "Oh No! Rory's intestines are hanging out, and a little kids are sneezing all over it! Johnson, grab me the torch! No, the OTHER one!"

    • by Kozz ( 7764 ) on Thursday April 05, 2012 @11:09PM (#39594157)

      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.

      Considering your profession, I'd think you would want to buy stock.

    • Re:No thanks. (Score:5, Insightful)

      by Doubting Sapien ( 2448658 ) on Thursday April 05, 2012 @11:16PM (#39594205)
      You take for granted the skin that acts as a physical barrier between the microbes that live on your body. For injuries such as severe burns and auto accidents involving road rash victims are not so lucky. This device sounds like an amazingly suitable solution that provides minimal interferance/physical contact. Although in this context, the irony of using a plasma to disinfect such wounds is not lost.
    • Re:No thanks. (Score:5, Insightful)

      by WCLPeter ( 202497 ) on Thursday April 05, 2012 @11:33PM (#39594313) Homepage

      I like the bacteria that lives on my body too... not so much the bacteria in the creek on the side of the road seeping into my open wounds thanks to the asshat who just cut me off.

      This kind of thing could be great for people who have allergies to anti-bacterial agents or, as the summary states, "provide a convenient way for paramedics and military personnel to deal with harmful bacteria in the field." If you're going to complain about killing off the good bacteria on your skin then rail about anti-bacterial soap and hand sanitizer, their daily use does far more damage to the good bacteria on your skin than any $100+ device used in an emergency will ever do.

      • Re: (Score:2, Insightful)

        I've never heard of anyone being allergic to an anti-bacterial agent. I've heard of latex allergies (from gloves) and allergies to some *perfumes* that are *added* to dissinfectants, but none regarding dissinfectants themselves. I do quite a bit of first aid stuff, so if you have any links to a source where I could find out if this is true (and specifically which chemicals are an issue), please post them.
        • Re: (Score:3, Informative)

          by WCLPeter ( 202497 )

          Based on nearly every emergency room doctor asking me if I have an allergy to Penicillin [] during the medical history part of the interview I figured it was an actual real thing. Still, just in case, I found this Wiki page talking about Penicillin drug reactions [] that covers allergic reactions and has links to some studies or some such thing.

          Honestly I'm not really well versed in the nitty gritty medical terms so I didn't entirely understand everything on the page, but I figure if its important enough for a d

          • Re: (Score:2, Informative)

            by Hognoxious ( 631665 )

            Penicillin is an antibiotic. When people speak of antibacterials they're usually referring to things you apply topically/externally, like iodine, alcohol, and peroxide.

            • Haptens (Score:5, Informative)

              by EdwinFreed ( 1084059 ) on Friday April 06, 2012 @04:19AM (#39595409)
              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.
              • I've definitely heard of the iodine issues, but is that the iodine itself, or the stuff they add *to* it to make it do other fun stuff (like the dyes, etc)? As for Penicillin, that is not the kind of thing I was talking about (as WCLPeter so graciously explained).
                • That's really the question, isn't it? Depending on what you read, you'll find people claiming that it's impossible to have an allergy to iodine itself and others claiming that it is. People have severe allergies to seafood, to iodine-based contrast material, and to povidone-iodine. But others point out that being allergic to one doesn't mean you're allergic to the others - there's some correlation, but it's small. And all of them contain other stuff.

                  As it happens my mother was also highly allergic to sh
              • by Shotgun ( 30919 )

                Ever poured alcohol or hydrogen peroxide on an open wound?

                DAMN!!! that hurts.

                This could allow for the disinfection of an open wound without sending the patient into shock.

        • I've heard of latex allergies

          Ew, must be painful...

          (from gloves)

          *sighofrelief* fortunately I'm not into fisting (but for those who are: that'll itch even more, at a less accessible place!)

          • Re:No thanks. (Score:4, Interesting)

            by Bill Currie ( 487 ) on Friday April 06, 2012 @05:24AM (#39595609) Homepage

            I had a friend who's allergic to latex. Forget the itch. Anaphylactic shock. When I asked him about the common use of latex being inconvenient, he said there were non-latex versions available.

            • It's not just "the common use" either - I have a scientist friend who has a latex allergy (daily exposure to lab gloves led to the development a few years after she finished her doctorate) who went into anaphylactic shock on two separate occasions - once (right after she found out) while blowing up balloons at her niece's birthday party, and once after eating food prepared by people wearing latex gloves (there was nothing indicating that the people prepping the food were wearing gloves).

              I always think bac

        • I'm allergic to sulphur based anti-biotics and topical application of a variety of sulphur compaunds commonly used anti-bacterial products. Anecdotally, my doctor tells me it's not uncommon, mostly causing mild skin irritation, but that my case is particularly severe. Beyond that I can't state a source...
        • Actually, about 30% of people develop a contact dermatitis due to neomycin, one of the three antimicrobials in triple antibiotic ointment.
      • by nurb432 ( 527695 )

        you're going to complain about killing off the good bacteria on your skin then rail about anti-bacterial soap and hand sanitizer, their daily use does far more damage to the good bacteria on your skin than any $100+ device used in an emergency will ever do

        Personally, i don't use either, as they are bad.

        However, i do agree, in cases where your skin is open, you do want to stop bad bacteria from entering and its an acceptable risk to burn off some good in order to stop the bad. ( be it a simple paper cut, sever cat scratch or being run over by a truck and your arm is danging..)

    • by epyT-R ( 613989 )

      this is meant for just such an occasion when the balance is unbalanced..

    • by sjames ( 1099 )

      How would you feel about a surgeon using one before opening you up?

  • With the prevalence of MSRA I've wondered why portable/handheld ozone generators have not become prevalent for hospital/clinical use. If this system is as effective it would eliminate the need for liquid suspension of ozone to prevent inhalation hazards. In fact, I wonder how long before other industries requiring sanitation abandon ozone systems in favor this plasma light system.
    • by virb67 ( 1771270 ) on Thursday April 05, 2012 @11:23PM (#39594247)
      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.
      • by nosh ( 213252 )

        MRSA is no the product of a total war on bacteria, but the product of a careless war.

        Our use of antibiotics is like sending a single policeman with a single gun to every incident reporting and not caring if they return. In most cases it will be enough, but in the long run there will be many criminals with police guns in their hands
        (and even if they do not need the new guns, they still get fresh ammo all the time).

        Hospitals are then favelas handled like that, i.e. sending one or two policemen with automatic

      • This used to be the case, but not anymore. Hospitals were (and still are) a breeding ground for resistant bacteria, MRSA included. These MRSA bacteria caused invasive infections (like pneumonia and bacteremia) that were very hard to treat and lead to many patient deaths. CA-MRSA (community-acquired MRSA) is a relatively new development over the last 10 years or so, and as the name implies, are typically contracted in the community. These bacteria are thankfully less invasive, but tend to cause a lot of
      • I don't think bacteria are not going to become resistant to these plasma "flashlights" any more than they are going to become resistant to alcohol, lysol, or autoclaves. They wouldn't be bacteria any more.
      • by cas2000 ( 148703 )

        no, MRSA is a direct result of the moronic overuse of antibiotics.

  • by Anonymous Coward

    For those with interest in the subject :

  • Real science, please (Score:5, Informative)

    by mpoulton ( 689851 ) on Thursday April 05, 2012 @11:14PM (#39594179)

    "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.

    • by Anonymous Coward on Thursday April 05, 2012 @11:59PM (#39594431)

      "It is also fitted with resistors and shit to stop it heating up and becoming too hot to touch."

      That better?

    • by Anonymous Coward on Friday April 06, 2012 @12:19AM (#39594509)

      Shaped like a flashlight? Really? It looks like a crayon.

      The article is (may need registering, but it's free to download for a month)

      The summary is semi-correct, but phrased terribly. The resistors provide enough ballast to limit the output power to 60mW. If you short the device the combined 100MegOhm is only going to dissipate a Watt of power. It's not so much to stop the device being warm to the touch, it's to stop the device from blowing up and/or burning your patient.

      If they weren't there then you're essentially trying to dump 10kV into a human body which is roughly 10kOhm to be conservative. The resistance of air is about a megaOhm per centimetre, but presumably if it's arcing due to the plasma it'll have negligible resistance after ionisation. What would probably happen is the DC converter would blow up, but you'd get a pretty nasty shock.

      Similarly as the human body has a maximum resistance of a few hundred kOhm, the plasma current is dominated by the two ballast resistors. Incidentally, it looks like the patient will either need to be wired up or will have to disinfect themselves because the thing works by pulling your body to ground with respect to the electrodes.

    • It is also fitted with resistors to stop it heating up and becoming too hot to touch.

      Maybe these are thermovariable resistors, that are used to detect when temperature is rising too high, and temporarily reduce power if/when it happens?

    • This is why I come to slashdot, and this alone.

    • by hey! ( 33014 )

      Yes, the authors have managed to write a sentence that is incomprehensible to people who understand electronics and people who don't, but for different reasons.

      Let me plays devil's advocate, though, and construe a speculative interpretation that might make sense.

      This thing generates plasma -- from what? Probably the air. So my guess is that it applies a pulse of high voltage to ionize the air, producing a plasma. Now suppose the plasma is too hot, what would adding a resistor in series do?

      Well, a resistance

      • note 1: air can be ionized or not, but I have no idea whether it can unionize.

        I fully support fair wages for air.

    • Yes! I knew someone would write a comment on that sentence. IANAEE, but I know resistors release heat when a current passes through them.

    • by sjames ( 1099 )

      Apparently, you are not one of those engineers you speak of. Otherwise, you'd know that since since power = I^2R and I = V/R, adding a resistor will reduce the total heat produced.

    • I agree with you the article is badly written.I would like to point out that some time ago i converted a USB ionizer which cost about £2 from ebay here:- [] This device generates a high voltage and a stream
  • Quick, where's the laser wrench? And the fusion shovel?
    • I don't know, but this sounds more like a lightsaber. Just crank up the power a little bit.
      • I don't know, but this sounds more like a lightsaber. Just crank up the power a little bit.

        Actually that is precise how the laser flashlights in Larry Niven's Ringworld (1970) operated. On a low setting they were pretty much flashlights. They were designed to be covert, non-obvious weapons. However if the power was dialed up you had a powerful energy weapon for slicing things at a distance.

    • Had to sell them to get a bacon stretcher and new muffler bearings.

      • In my Universe[1], I would let you slide on the muffler bearings, BUT the bacon stretcher is just taking things too far!
        Repent your evil ways and use a bacon condenser instead.
        Just think, put in 10 kilos of bacon, and get a handful of bullion cube sized bacon bites!
        Density FTW! (just ask my bathroom scales!) ;-)

        All hyperbolic humour/sarcasm aside......a 'bacon stretcher'?
        That's a new one for me, first time I've encountered that one...Thanks! :-)

        [1] I am the Emperor of my fantasy Universe, so I get to make

        • You never worked at a restaurant? Maybe it's just breakfast restaurants. Between looking for the non-existent attic/basement for a non-existent bacon stretcher and figuring out how not to tap the grease trap in the parking lot(big mess), it's amazing I passed my 1st week dish dogging. Luckily I did, good times were had... If my parents only knew.

          • by rts008 ( 812749 )

            I've worked in many restaurants [including family owned], and still have never heard of that particular device. :-)

    • It's all about the hyperspanners.
  • by Anonymous Coward

    It is the CSIRO again!

  • I'll take two! (Score:3, Interesting)

    by JudasPreist ( 2530344 ) on Thursday April 05, 2012 @11:37PM (#39594335)
    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.
    • you could sanitize the hands of a hundred people in like a minute!

      If they make a BFG [] version of it you could sanitize the entire bodies of a whole roomful of people in like seconds! ;)

    • That would be great. Now I can leave the bathroom with sanitized poop on my hands.

      • That would be your left hand, right?
        • Toilet paper dispensers are usually on the left, and somehow I've just never managed to try and work from the other side. I fear your strange fascination with my wiping habits.

      • Notice I didn't say that the sinks would be removed. You would have plenty of opportunity to rinse off, then use the plasma flashlight or whatever clever patented name they create for it and then dry off somehow. The material in question would be removed, and any remaining bacteria dead, but maybe they should make you drip dry your hands as a penalty for being clumsy and getting material on your hands.
        • It's still much easier with soap. Just no need for disinfectant soap. And I still don't get how it replaces a towel either.

  • Something Fishy (Score:3, Insightful)

    by davetv ( 897037 ) on Thursday April 05, 2012 @11:49PM (#39594379)
    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.
  • by Anonymous Coward

    They sell this hand held battery powered bacteria killing U.V. light at Fry's electronics. As shown on T.V.!!!

    Ironic, my captcha is 'emitted'.

  • by gcnaddict ( 841664 ) on Thursday April 05, 2012 @11:59PM (#39594429)
    Old Dominion University did this nearly a decade ago and filed a patent for it. I see no reference to them in the article. []
    • by Anonymous Coward

      The pencil that you cite requires a gas source so they aren't using identical techniques to generate the plasma:

  • by Anonymous Coward

    I can see these replacing all those tedious hand-dryers in public toilets now - blast your bacteria and virii away in seconds!

  • Which means with enough middlemen, the standard good old boy networking, and the proper paperwork, the US Military will be paying somewhere between $7000-$9000USD each in large quantities.

    Yeah for the 1%er's!

  • by PPH ( 736903 ) on Friday April 06, 2012 @01:09AM (#39594731)

    ... popups that block the !@%$#*& article?

  • by Hognoxious ( 631665 ) on Friday April 06, 2012 @01:18AM (#39594763) Homepage Journal

    I wonder if it would work on walls? We have some persistent fungus in parts of our house. Bleach the bastard and in a few weeks it's back.

    • Hey, when shopping for a house in Santa Fe, I paid a few hundred bucks to a very professional Assessment for Microbial Contamination from Dan Stih of It included counts of a variety of classes/species of fungus hanging out outside and contrasted that with the air quality in various parts of the house. It then honed in on physical penetration tests of surfaces like wood, tile grout and drywall, with an detailed recommendation for a remediation protocol.
      I was very satisfied with

    • by rts008 ( 812749 )

      I forgot to add:
      don't overlook any HVAC duct-work as a source!

  • Which is better? (Score:1, Interesting)

    by Anonymous Coward

    I wonder if the bacteria that live on my skin stop more germs than my immune system. I suspect so since they have the numbers. It is sad that I can't find a bar of soap that does not have anti bacterial stuff in it. Germophobes have come down with some nasty fungal infections after ridding their skin of bacteria. It sounds useful for treating that missing patch of skin that time I left it on the goose poop decorated bike path. That one started to show sign of blood poisoning.

    • by rts008 ( 812749 )

      I don't recall specifically any info on skin bacteria, but many species of bacteria use chemical warfare to combat rivals and competition.

      In addition, mostly they seem to rely on the 'crowding out the competition' tactic that weeds use on grass and gardens...'consume all the resources to deny your enemy a foothold'.
      It's a proven and valid strategy for most species of all orders(not just bacteria), historically.

      Trivial/arcane fact:
      40%-65% of the volume of 'the average human turd' is dead bacterial corpses fr

  • by Anonymous Coward

    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

    Hmmm thanks, but I'd prefer to sit tight until we know exactly how it does this. I know it has probably gone through rigourous testing etc., but if we've no idea how it works we've no idea how it could be causing other damage. We used to think throwing antibiotics at every possible problem was a great idea until we discovered transmiss

    • by michelcolman ( 1208008 ) on Friday April 06, 2012 @05:46AM (#39595679)

      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?

      • The thing produces free radicals, which are molecules with unpaired electrons. Since electron really prefer to be paired, a free radical will catch an electron from any nearby molecule, turning the later into another free radical. Each time a molecule from a cell is touched by this chain reactions, it is damaged and will need repair. This is true for microbes, but for human cells as well

        Cells have defenses. Molecules such as Vitamin C and E, Glutathione, or the SuperOxyde Dismutase enzyme, will be able to e

    • Ozone and free radicals – very bad for bacteria. Further, this is not plasma, this is corona. Plasma is fully ionised gas. Corona on the other hand is an area or volume of week discharge through a gas – which is what this is. So this is a pen shaped thing with a week high frequency ~20kV discharge, almost certainly capacitivly coupled to the output to limit current. If it isn’t capacitivly coupled or otherwise current limited – hello RF burns!
  • So this is a flashlight whose sole purpose is to shine on your flesh. I'm pretty sure there's already a product called a Fleshlight.
  • I could build several UVC-LED flashlights for that much and get the same effects with better lifetime, durability, and portability.

  • When it grows up, it will be a light saber.
  • Should be called the Fleshlight! Yeah, since it's a flashlight to be used on the flesh, right? ;-) I wonder if it feels real good....
  • For when soap is just too simple...
  • by Benfea ( 1365845 ) on Friday April 06, 2012 @03:38PM (#39601007)
    You evilutionists can't fool me! Everyone knows diseases and infections aren't caused by "invisible tiny creatures", but by demons! You are just trying to fool everyone into buying your useless devices so you can raise more money to promote your atheist-satanic-Muslim agenda! Admit it! [/tongueincheek]

"If it's not loud, it doesn't work!" -- Blank Reg, from "Max Headroom"