Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 


Forgot your password?
Close
typodupeerror
×
Science

Bacteria-killing Pencil 285

Posted by Hemos from the destruction-of-those-around-us dept.
kahrytan writes "Mounir Laroussi, a researcher at Old Dominion University has invented a hand-held device that is dubbed a plasma pencil. The pencil generates a "cold plasma," which can be used to kill germs that contaminate surfaces, infect wounds and rot your teeth. In the future, it might be used to destroy tumors without damaging surrounding tissue. When he turns the pencil on, it blows a high pitched whistle as a glowing, blue-violet beam about 2 inches long instantly appears at one end. Stick your finger in its path and you only feel a cool breeze, but the beam is powerful enough to blast apart bacteria that's crawling on your skin. Such a device if patented, tested and mass produced could end up doing a lot of good. Disinfecting surgery tools, keeping open wounds open in hospitals, destroying tumors in hard to operate areas like brains, and even treating that simple paper cut. The story can be read at dailypress and old dominion university."
This discussion has been archived. No new comments can be posted.

Bacteria-killing Pencil More

Bacteria-killing Pencil

Comments Filter:

  • Patented? (Score:5, Insightful)

    by RAMMS+EIN ( 578166 ) on Saturday October 15, 2005 @09:55AM (#13796956) Homepage Journal
    ``Such a device if patented, tested and mass produced could end up doing allot of good.''

    Even if not patented, it could do a lot of good. Possibly even more.

    • Why it's no good without a patent. (Score:5, Insightful)

      by G4from128k ( 686170 ) on Saturday October 15, 2005 @10:23AM (#13797087)
      A device such as this will require clinical testing to prove that it is both safe and effective. Those tests will take on the order of 2 to 5 years and cost on the order of $25 to $200 million for each proposed use.

      Who is going to spend that kind of money if the minute they get approval, some other company can sell these devices without the clinical testing costs? The company that performed the tests will need to add $25 to $200 to the price of the device (in addition to manufacturing costs), assuming they sell a million of them. And the competitor will be able to undercut the first company on price.

      The math is even worse on a risk-adjusted basis because so many promising products fail during testing. Thus, the costs of developing several failed devices must be paid for by each successful device.

      Until governments foot the bill for all medical R&D and clinical testing, patents are a crucial part of the medical device & pharma industry.

      The point is that without a patent, nobody will pay for testing, the device will sit on a shelf, and it will do no one any good. This is why pharma and medical devices will never be like OSS -- the invention of the first instance is an extremely minor part of the cost of development. Building a better medical mousetrap is nothing. Proving it is safe and effective and gaining govt approval is everything.

      • Thanks for posting that, especially because you included the ``Until governments foot the bill for all medical R&D and clinical testing'' bit. At this point, I spent a long time thinking about how to describe your post, and I think I found it: balanced.
      • Isn't this a bit flawed. Isn't it so that each implementation must be put through testing thus if company A puts an implementation through testing company B still needs to go through testing with their implementation? Had B made an exact copy of company A's implementation then they would be infringing on A's copyright (or some other similar law.) And even if they created an exact copy wouldn't they still need to go through testing to get their copy approved? Thus both company would compete on equal terms, p

        • Had B made an exact copy of company A's implementation then they would be infringing on A's copyright (or some other similar law.)

          Copyright does not apply to processes. "Some other similar law" in this case would in fact be patent law. For example, one way to "evergreen" (extend a useful lifetime of) a drug patent is to patent the chemical once it works in rats and rabbits, patent an improved invention incorporating the chemical a few years later, and then submit the improved invention in the New Drug A

      • Cheap devices are quickly tested and proved. (Score:5, Insightful)

        by twitter ( 104583 ) on Saturday October 15, 2005 @11:16AM (#13797308) Homepage Journal
        A device such as this will require clinical testing to prove that it is both safe and effective. Those tests will take on the order of 2 to 5 years and cost on the order of $25 to $200 million for each proposed use. ... The point is that without a patent, nobody will pay for testing, the device will sit on a shelf,

        I doubt this will sit on the shelf long. A big dumb company might spend that much money testing out something that costs far more than this does. A cheap gadget like this will quickly be tested in every conceivable way by hungry graduate students at every University in existence like TLDs were. The results should start pouring out soon unless some jackass gets a pattent and demands fees which eliminate any price advantage the device has over mercury vapor lamps. In that case, we will have to wait another seventeen years and then some.

        Until governments foot the bill for all medical R&D and clinical testing, patents are a crucial part of the medical device & pharma industry.

        There's enough red tape as it is. Please don't make me go Federal for everything. Let them compile, analyze and publish statistics other people generate. Laws protecting patient privacy are fine. Making every institution apply for a Federal Grant just to buy a $50 device would be really stupid.

        There may indeed be some non-obvious and inventive tricks in this device that deserve a patent. If so, we can hope the inventor licenses things out at a price that will insure widespread adoption and great riches for himself. If not, we can only hope that they don't get any patent and everyone can start testing.

        • A cheap gadget like this will quickly be tested in every conceivable way by hungry graduate students at every University in existence like TLDs were.

          I'm sure that grad students can do so valuable preclinical work -- showing that exposure to this devices doesn't cause cancer in human cell cultures, showing that the device kills X% of type Y bacteria with Z seconds of exposure, etc. But that won't get the FDA's approval. Where do the grad students get the money to test the device on 1,000, 10,000, or 100,

      • > Until governments foot the bill for all medical R&D and clinical testing... Governments do not have money to foot the bill for anything. God, I really wish people everywhere would realize that ALL governments operate with TAXPAYER money. In the U.S., if you ask people around you how much they paid in taxes last year the majority will say something along the lines of "I didn't pay anything, they payed me X dollars." Everyone everywhere should get the mindset that every single dollar, pound, yen,
        • Governments do not have money to foot the bill for anything. God, I really wish people everywhere would realize that ALL governments operate with TAXPAYER money.

          Actually, government doesn't run on tax dollars alone, but rather Government debt.

          From http://en.wikipedia.org/wiki/U.S._government_debt [wikipedia.org]

          As of August 2005, the total government debt is approximately $7.9 trillion, i.e. $7,900,000,000,000 ($7.9 × 1012). This is more than ten times the amount of United States currency in circulation as of 2005, e

      • medical patents are harmful (Score:5, Insightful)

        by idlake ( 850372 ) on Saturday October 15, 2005 @11:24AM (#13797345)
        Until governments foot the bill for all medical R&D and clinical testing, patents are a crucial part of the medical device & pharma industry.

        Governments (i.e., tax payers) effectively already foot the bill for a lot of drug and medical device development, even development that leads to proprietary, patented, commercial products. Furthermore, since the monopoly prices that result from patents end up being paid by government-supported health-care plans, they end up paying the rest of it, too, many times over.

        In addition, the market is doing a piss poor job in creating incentives for companies to create the drugs that people actually need; companies have an incentive to create useless variations on medicines that treat symptoms of common diseases but don't cure them. What we actually need are medicines for currently untreatable diseases and medicines that cure.

        Finally, a lot of the costly approval process is only in place because of the commercial development model; for many reasons, private companies are prone to bringing dangerous drugs to market without close government supervision. For drugs and devices developed with public funds, the approval process can be greatly simplified.

        Overall, it would almost certainly be more cost effective for everybody to abolish drug and medical device patents altogether, have government and scientists set the goals for what to develop, and have all research, development, and testing of such devices paid for by the tax payer. Private companies can still get involved through contract work and work-for-hire.
        • Overall, it would almost certainly be more cost effective for everybody to abolish drug and medical device patents altogether, have government and scientists set the goals for what to develop, and have all research, development, and testing of such devices paid for by the tax payer. Private companies can still get involved through contract work and work-for-hire.

          The assumption being that since government monopolies have failed to produce cost-effective innovation so many times before, the model is due fo

      • "Until governments foot the bill for all medical R&D and clinical testing, patents are a crucial part of the medical device & pharma industry."

        I'm glad to see that you're not promoting government funding, even though the patent office is overburdened and sloppy. There are two things wrong with government funding.

        1) Decisions about which products even get funded for the approval would be given to bureaucrats. Even if they were consistently knowledgable, they have no real pressure to get it right
      • Who is going to spend that kind of money if the minute they get approval, some other company can sell these devices without the clinical testing costs?

        The US Military
    • Actually by the sound of it, this is an actual novel and non-obvious invention. It's one of maybe a dozen items this year that are rightly patentable. It's the other 99% that is BS. :-)

      So yeah, let's get rid of software patents but keep patents for something actually useful, like this. :-)
    • ... about their "room temperature" though. From the article:

      But the plasma pencil's plume is just 34 degrees Celsius (75 F), which is about room temperature.

      Isn't that roughly twice normal room temperature? Who here has their room as hot as 34 degrees C?
      • 34 degrees C = 93 degrees F, so there seems to be a unit conversion problem here.
      • Who here has their room as hot as 34 degrees C?

        I do. But I work 1200m underground in a lead mine, and where I live regularly tops 45 degrees in the shade in summer, so perhaps I'm not representative of the normal slashdot population.

        And I thought room temperature was in the order of 25 degrees C or so.
        Maybe they're trying to compare it to your typical plasma temperauture, which is in the order of 4000 degrees C.

      • 24C is 75F. I'm betting it was just a typo.

  • It's only a matter of time (Score:5, Funny)

    by cloak42 ( 620230 ) on Saturday October 15, 2005 @09:55AM (#13796957) Homepage
    before we see light sabers.

  • FINALY (Score:2, Funny)

    by Anonymous Coward
    now I can kill these annoying crabs at home without risk of serious injury

  • Ah... (Score:4, Funny)

    by Black Parrot ( 19622 ) on Saturday October 15, 2005 @09:59AM (#13796976)
    A light sabre for sanitation freaks.

  • Cool! (Score:3, Funny)

    by FlyByPC ( 841016 ) on Saturday October 15, 2005 @10:00AM (#13796981) Homepage
    If he really wants to give it a workout, he could always try it on whatever that sluggishly-flowing brown stuff is in the Elizabeth River on the west side of campus...

  • How come it only hurts the bacteria? (Score:3, Interesting)

    by Anonymous Coward on Saturday October 15, 2005 @10:01AM (#13796989)
    I don't understand how this can blow apart bacteria but not blow apart your skin cells. Can anyone explain? Also, why call it a pencil? It doesn't write anything. Might as well call it a stick, rod, or magic wand perhaps.
    • It says it might be used to destroy tumours without damaging the surrounding tissue. How does the beam know which cells are bad and which aren't? I smell a rat.

    • Re: How come it only hurts the bacteria? (Score:5, Funny)

      by Black Parrot ( 19622 ) on Saturday October 15, 2005 @10:12AM (#13797035)
      > Also, why call it a pencil? It doesn't write anything.

      If you work in a biolab you could draw pictures in the bacterial cultures with it.
    • I don't understand how this can blow apart bacteria but not blow apart your skin cells.
      Because the epidemis of your skin is made of dead cells... You can't kill what's dead already... :)

      And bacterial cell membrane are a lot more fragile than the dead cells of your skin.

      • Why do people think this invention is so interesting?

        It cleanses the surface of the skin of bacteria. There are already a huge number of cheap ways to do the same thing (alcohol, hydrogen peroxide, uv lights).

        So is this cool just because it takes batteries and looks like light sabre jr?

        --Pat
    • Because if people think of it as a pencil they are more inclined to put it in their mouths and destroy all that nasty bacteria on their teeth. You see, sometimes, with clever branding and naming, there's no need for a manual!

  • Wow! (Score:5, Funny)

    by Chocolate Teapot ( 639869 ) on Saturday October 15, 2005 @10:04AM (#13796997) Homepage Journal
    It must be really sharp! I mean, those bacteria are pretty small.
  • ... Looked suspiciously like a salt shaker.

    The applications for dentistry might be interesting.

  • The fine print. (Score:4, Funny)

    by Black Parrot ( 19622 ) on Saturday October 15, 2005 @10:09AM (#13797015)
    "May cause you to turn green and grow a second head. May cause addiction in persons with neurotic fixations on sanitation. For external use only. Not for use by children under 40. Erotic applications may violate the Sex Toys Act of 1986. Batteries not included."
  • While this is a cool invention, it is clearly being over-hyped. If you RTFA, the device develops a jet of oxygen radicals. Somehow this stream of highly reactive particles is supposed to cause "no harm, when it is directed at human skin" (from the Old Domion link). But "the beam is powerful enough to blast apart bacteria that's crawling on your skin" (from the Daily Press link), and "such a device could destroy tumors without damaging surrounding tissue" (from the Old Dominion link). --- If the device can r
    • I was wondering the same thing. If this thing can blast the cell walls of bacteria, why couldn't it do the same to other cells?
    • The outmost part of the skin is made of dead cells. You really can't kill them twice. Seriously.
    • I think the secret distinguishing method of only killing bad cells is: "if it's alive, it's bad." That works fine for use on the epidermis. If you can heat a living cell enough, the liquid inside expands, boils, and ruptures its membrane and the cell dies of 'catastrophic disassembly.'

      As far as a wound goes, I wonder if it would be appropriate there. Pouring antiseptic on a wound often does as much harm as good, since it kills cells indiscriminately. I remember reading about WWI era wound treatment, an


    • We already have devices that sterilize inert medical instruments quite efficiently-way more efficiently than waving a tiny beam across their entire surface area. It may have a niche for sterilizing items that are temperature sensitive (and not overly sensitive to highly reactive charged particles). But it clearly won't be a "miracle beam" that can kill bacteria in a wound while leaving healthy tissue unaffected.

      I dunno about other applications, but if they can make this efficiently clean larger areas, my em
    • To be honest killing bacteria on the skin is not that hard - just a little betadine(iodine) or chlorhexidine and the skin is sterilized for surgery (mostly). Bacteria hide out in hair follicles, cracks, etc, and this device seems quite costly to do what a cheap wash will do. ANyway, that's not the point - it's the antibiotics given during the operation that kill off the bacteria, that allow us to operate safely.

      As far as this being used to remove tumor cells, I again think this won't be usefull. Often tu

  • "This invention is yet another testimonial that Dr. Laroussi and his colleagues in the college think boundlessly when it comes to applying such disruptive technologies so innovatively."


    Phrases like that make my pet goat puke.

  • That kinda sounded like a mini lightsaber that can heal people.

    You know...if you made the beam superheat things instead of cool them and about 3 feet longer, it would STILL kill bacteria and be a helluva lot cooler!

  • does not blow apart bacteria (Score:5, Insightful)

    by cinnamon colbert ( 732724 ) on Saturday October 15, 2005 @10:15AM (#13797045) Journal
    basically, this device produces a bleach like gas that chemically inactivates surfaces; it inactivates the outer layer of your skin just as much as the bacteria, but since the outer layer is dead skin cells it does not matter

    fta, it produces highly reactive oxygen spiecies.

    If such chemicals, such as peroxy radical, superoxide, etc are in fact produced, then to the extent that they get past your outer skin and react with live cells, the chemicals will produce cancerous and mutagenic lesions. If the chemcals get to the layer of living cells which is continously gowing and dividing to produce new skin, you would have to worry about skin cancers......

    Cold plasmas are of great use in modifiying surfaces, eg this pen might be perfact for grafitti removal, activating plastic so paint will stick (the activation of polyolefins like polypropylene is a big business) ...lots of other uses

    what has held back the cold plasma industry is the lack of cheap devices to play with; i have had to pay hundreds of dollars to have small (mouse sized) objects treated for a few minutes
    • "If such chemicals, such as peroxy radical, superoxide, etc are in fact produced, then to the extent that they get past your outer skin and react with live cells, the chemicals will produce cancerous and mutagenic lesions. If the chemcals get to the layer of living cells which is continously gowing and dividing to produce new skin, you would have to worry about skin cancers......"

      What tosh. By this reasoning the hydrogen peroxide solutions available in every drug store in the world are horribly carcinogenic

  • natural selection (Score:5, Insightful)

    by handy_vandal ( 606174 ) on Saturday October 15, 2005 @10:17AM (#13797054) Homepage Journal
    ... the beam is powerful enough to blast apart bacteria that's crawling on your skin.

    Good news if it blasts 100% of the bacteria, 100% of the time.

    Potentially bad news if it only blasts 99.999999% of the bacteria, thus selecting for super-tough microbes.

    -kgj
    • You certainly don't want to have a bacteria free skin. That's when you'd likely have some really nasty stuff settling in.

    • Not necessarily (Score:4, Interesting)

      by Kris Warkentin ( 15136 ) on Saturday October 15, 2005 @11:12AM (#13797292) Homepage
      The difference is, antibiotics kill the weakest germs first so if you stop too soon, you're breeding stronger germs.

      This would most likely kill the most accessible germs first or if nothing else, just kill the ones it was used on. ("Hey Doc, I think you missed a spot"). I suppose it's also possible that germs with stronger outsides might be given an advantage but it doesn't seem quite as obvious as with drugs.

      cheers,

      Kris
      • This would most likely kill the most accessible germs first or if nothing else, just kill the ones it was used on. ("Hey Doc, I think you missed a spot"). I suppose it's also possible that germs with stronger outsides might be given an advantage but it doesn't seem quite as obvious as with drugs.

        Good points.

        We might want to isolate and breed super-tough bacteria -- say for use as interstellar messengers, capable of surviving indefinitely in hard vacuum. Give the little boogers photosynthetic capabili
    • I think this is a valuable line of thought, but ultimately a non-issue.

      In killing bacteria with cold plasma, I'm hypothesizing that you'd be selecting for properties which are almost certainly either not correlated with, or negatively correlated with, what we'd normally count as "fitness" in bacteria. The better they are at surviving cold plasma, the worse they will be at being bacteria.

      Of course, mass bacteriacide always has the chance of producing super bacteria. It was originally thought that our widespr
    • Potentially bad news if it only blasts 99.999999% of the bacteria, thus selecting for super-tough microbes.

      Sure, but as long as we're SWAGing, it could also leave bacteria behind who have such thick outer membranes that they were crippled in the first place. (i.e. they were not viable before, and still aren't)

      The maxim "whatever doesn't kill you makes you stronger" doesn't necessarily apply to evolution. It's too complex.

  • Bioterror Agents (Score:5, Insightful)

    by MidoriKid ( 473433 ) on Saturday October 15, 2005 @10:20AM (#13797075)
    The article claims it can be used to "mop up bioterror agents". Is anyone else sick of how every new invention is measured by it's usefulness to fight terrorism?
    • Thats how you get funding in todays society..
      • Thats how you get funding in todays society.
        In today's United States. Europe isn't suffering even a tenth of the fear that the US keeps insisting on.

        --
        Waging war against fundamentalism is as likely to make the fundamentalists give up as 9/11 was likely to make the US give up.

    • Re:Bioterror Agents (Score:4, Insightful)

      by RAMMS+EIN ( 578166 ) on Saturday October 15, 2005 @10:47AM (#13797186) Homepage Journal
      ``The article claims it can be used to "mop up bioterror agents". Is anyone else sick of how every new invention is measured by it's usefulness to fight terrorism?''

      Yes, and I have been sick of it from almost the moment it started. People, 9/11 was shocking, but it was just _one_ event! People in other places are confronted with terrorism all the time, and most are a lot cooler about it. And why wouldn't they? It's not like you can ever make security tight enough that no terrorist could get through; the only thing it is sure to accomplish is inconvenience and deterioration of civil liberties for everyone else. All to protect you from something that is less likely to kill you than your diet, the traffic, or suicide.

      My advice? See terrorism for what it is; a minor threat to your safety brought about by fanatic maniacs who are angry about some (imagined or real) wrong your country has done to them. Get on with your lives, and don't let anybody (terrorist or politician) scare you into believing you need to sacrifice anything for your safety.
  • Such a device if patented, tested and mass produced could end up doing allot of good.

    I had an English teacher called Mrs. Allot once. She was most definitely Allot of Bad, though...

  • A little etymology (Score:5, Funny)

    by Lars T. ( 470328 ) <{Lars.Traeger} {at} {googlemail.com}> on Saturday October 15, 2005 @10:59AM (#13797236) Journal
    The words pencil and penicillin both derive from the same word penicillum, which is a double diminutive of the latin word for tail. I will not name that word, else I'll be modded Troll ;-)

  • How it Works: (Score:2, Insightful)

    by TadZimas ( 921646 )
    I'm not a bio major or anything (yet) but here's how I assume it works: The stream of 'cold plasma' is just energized oxygen and helium, packing extra electrons. When it comes into contact with a bacteria, it oxidizes the bacterias cell wall, causing them to lyse. Bam, no more bacteria. There isn't any real danger of the bacteria evolving an immunity, as we've been throwing similar tactics at them for a long time, and you probably have some in your home: Hydrogen Peroxide functions on basically the same pri
  • They said the same thing about X-rays, too. How safe they were particularly.
  • Conversation over holophone. Mother: Jimmy got suspend suspended again.. Father: God dammit WHY ? Mother: He's sprayed the #2 Plasma pencil on little Roberts 3th eye. He lost it so we have to pay for the growth of a new one. Father: OMFG. Mother: It's gonna cost 893748934 credits Father: Im gonna send that kid to earth... blah blah.

  • Wine Making (Score:4, Informative)

    by purduephotog ( 218304 ) <hirsch@inorbitSLACKWARE.com minus distro> on Saturday October 15, 2005 @11:35AM (#13797407) Homepage Journal
    I make wine and my wife makes beer in our home. The current sterilization procedure for bacteria prevention involves the following:

    1) Rinse out container with hot water
    2) Soap out container (dishwasher soap) with awkward brush. Get all surfaces well wetted.
    3) Rinse 3x to remove soap residue
    4) Bleach container to 1% in hot water and let sit for 1 hour (massive headaches- bleach fumes- vent out the window)
    5) Rinse container 4x to remove bleach residue
    6) Mix Sodium Metabisulfite and Citric Acid in 1:1 ratio and coat all surfaces inside container for 30 sec - 1 minute. Fumes are nose + throat searing
    7) Rinse 4x to guarantee removal.
    8) Cap with plastic.

    Takes about 1.5 hours for 2 jugs to go through the entire procedure.

    Give me a portable plasma generator that can do the entire surface and I've just increased my productivity significantly as well as having less time downstairs and more time drinking the 'fruits' of the labor.
    • 70% ispropanol kills just about everything, including fungus and will keep them from sporulating (don't use a higher % than that or they will form spores and can then grow later on). You might want to try the soap, to remove the greases/oils and then the alcohol - just slosh it arond and then let it air dry.
    • Or, just get some Iodophor. There's a good article about Iodophor here: http://hbd.org/franklin/brewinfo/iodophor.html [hbd.org].

      Iodine does quite a good job at sanitizing, and at 12.5 ppm needed for sanitization, it's well under the taste threshold.
    • You should be using potassium met. Also you don't say the amount of water. The citric acid levels are way too high. You can cut to about a 1:5 ratio.

      IE. 1 tsp met with about 1/5th tsp acid or acid blend in 1/2 gallor or 2 liters of water is fine. Then for the wine you don't need to rince with water after and you can usually skip the soap / detergent cleaning protocol.

      If the carboy is clean to start with just sterilize it. If it is dirty usually a clorine based soap product such as diversol will do a m
  • I RTFA and looked at the picture, which looked Photoshopped. And while cold plasmas exist, what they described is not a cold plasma. And really, how does a stream of oxygen radicals distinguish between bacteria and human cells? It all sounds too good to be true, and I think it IS too good to be true.
  • Remember the one about the doctor wandering around a hospital with a thermometer tucked behind his ear? Someone points it out to him, and he says 'Damn, which arsehole has my pencil?'

    Well, they just ruined that joke...
  • (I still can't believe nobody has said it yet - is it because it's saturday?)

    I, for the honor of the underrated /. cliché jokes, welcome our new bacteria-killing overlords.

    (Applause)

    Thank you.
  • "blast apart bacteria that's crawling on your skin." expands to "blast apart bacteria that is crawling on your skin."

    Which should be "blast apart bacteria that are crawling on your skin"

    All I ask is that journalists be literate; you know, tell possessive apostrophes from contractions, singular from plural, stuff like that. Is that too much?

Slashdot Top Deals

Understanding is always the understanding of a smaller problem in relation to a bigger problem. -- P.D. Ouspensky

Close