PLASMA GERM BLASTER GUN invented for cleaning skin A handheld plasma blaster that can beam away 17 layers of bacteria could be used in medical emergencies to clean skin and wounds, said a physics boffin presenting the device in the Journal of Physics D: Applied Physics today. The plasma gun or "flashlight" requires just a 5V battery to produce enough cold plasma to kill even …
Sounds good, feels good. This could go far.
Only thing that I wonder on anything that kills bacteria is that even if they don't kill them all then you have created more space for the realy bad ones and if you do kill them all you've made space for new bad ones. Evolution is not limited to humans I hear.
What you do is the 'competitive exclusion' method. Once the bacteria you want dead is gone, you spray known good bacteria in its place. These out compete with other species by sheer numbers.
People use this method in waste control plants and in the Aquarium/pond hobby to greatly reduce disease causing bacteria. Works too.
Be kind of cute to see a nurse armed with a ray gun killing a room of bacteria! :)
Nearly a decade ago I saw a BBC News web article about plasma, and how it was to be used for space travel (Deep Space 1 test probe), medical hygiene (sterilise instruments, similar to this story - aha, http://news.bbc.co.uk/1/hi/health/2984843.stm), and that it's possible use plasma as a shield to reflect, or perhaps rather to absorb and disperse/defocus, EM energy (i.e. lasers) in space (due to no atmosphere to disrupt plasma).
When I tried to find the combined article again to show a friend, it had disappeared, and all I could find was the ion drive and medical stuff.
Has anyone else seen anything about the latter defensive use of plasma? Always seemed like a good one for satellites, given China's demonstrated ground->space laser tricks.
Plasmas have certainly been tried as a means of radar stealth for aircraft (i.e. absorbing/shielding from EM emissions) - see for example
https://en.wikipedia.org/wiki/Plasma_stealth#Absorption_of_EM_radiation
http://defensetech.org/2006/03/30/stealths-radioactive-secret/
It's also been proposed as a means of "inflating" a magnetic field to act as a (very) lightweight solar sail:
https://en.wikipedia.org/wiki/Magnetic_sail#Mini-magnetospheric_plasma_propulsion
http://www.ess.washington.edu/Space/M2P2/STAIF2000.PDF
The last thing you want near a human is ozone. It's toxic at the smell threshold. With luck the sort of machine you refer to smelled of oxides of nitrogen rather than ozone (not that you want to breath them either, but at least they're less toxic).
This plasma device sounds interesting, but will it fail in the same way as aqueous bactericides? You can't zap the blighters if they've got a protective coat around them. In the case of skin, it's not a shiny surface with a thin film of bacteria on it. The surface of skin is a messy, porous construction of dead skin cells with bacteria in the spaces between them. Those bacteria are well protected. That plasma had better be able to penetrate further than 25 micrometres. I'd rather my would-be surgeon scrubbed with povidone iodine.
"Violet ray" and "violet wand" devices do generate ozone, as (IIRC) does anything else that produces an electrical arc in air.
Fair point regarding biofilms on the skin surface -- it's an open question, at least here among the commentards, whether the test described by the researchers had any relationship to the situation that'd be found when attempting to kill bacteria on human skin. I don't have time to read the paper, even if it's available without a damned journal subscription; if someone else does, I'd be interested to hear the result.
layer of dead cells -- if it takes five minutes for this thing to burn through 25 micrometers (that's .025mm) of E. fecalis biofilm, it doesn't seem too likely to go through human tissue like an electric carving knife, does it? You'd probably be safe enough using it to clean your teeth -- in fact, I can see that being an excellent application of the technology, dental biofilms being the incredibly resilient things that they are.
That is why I don't think that it's really a plasma, but is an ion beam. High voltage (and low power) ion generators have been in use for a while as air purifier/fresheners, the idea being that the ions induce chemical dissociation of nasty smelling substances in the air.
The same principle (in a directed ion beam) would damage bacteria enough to kill them.
A plasma is a very, very hot state of matter in which the thermal energy is so great that the electrons are knocked away from the nucleus and keep getting knocked away even if they manage to recombine due to electrostatic attraction.
If an electron gets ripped from a nitrogen or oxygen molecule in the air and then gets blown away in a gentle breeze by electrostatic repulsion from the electrode that caused this, then that is a different state of matter. A collection of ions is not a plasma, but a plasma is a (very hot) collection of ions.
I have felt the gentle breeze coming from an ion generator as it blew over my fingertip. I would not want to feel a stream of plasma blowing over my fingertip. Hence my trying to draw the distinction.
From the paper: "This handheld plasma jet is driven by a 12 V battery... With the input
voltage of 12 V, the output voltage of the dc booster reaches 10 kV. An array of 12 stainless steel needles is used as an electrode. The radius of the needle tips is ∼50 µm. The ballast resistors R1 and R2 (both 50 M ) are used to limit the discharge current. This is made to minimize the plasma heating and electric shock effects on the human body and to make it safe to touch"
Again: Five minutes to go through twenty-five micrometers (.025mm) of biofilm -- for comparison, that's about half the diameter of an average human hair. If the mess you're cleaning up is thick enough to be clearly visible on the surface of the toilet, you're going to need to bathe it in plasma for so long that it'd be much more worth your time to put on a pair of kitchen gloves and just scour the bloody thing.
Also: Yes, I see what you did there. I do not approve.
People often don't realise that bacteria builds skyscraper layers of membranes many layers thick. So whilst the top layers die from exposure to chemicals, light, etc. the under layers remain untouched. Which is why you need to scrub hard!
Then one could assume that it would takes much longer than that to get through even 1mm of something like human skin. Knowing that, we could assume that it would probably be safe for humans to be exposed to this for up to several hours. Assuming that to be true, this would be brilliant in public restrooms; any given person is only going to spend less than an hour a day in there, but all the bacteria left behind would be burned to a crisp. Similarly, kitchen counters could have a device like this situated over them, as could drinking fountains, even keyboards or public telephones (do those even exist these days?).
Burned to a crisp, hhehehee... Just as long as they are not burned into CRISPS.... Wouldn't want THESE to be recycled into snacks...
Would give a whole new twist (not the Twists snack, mind you, hhahaha) on "Soylent Green is PEOPLE"... Just recycle the detritus left behind and have trucks vacuum it up like the ones that steal used cooking oil from behind restaurants.
Butt ass for 5 minutes, this tech could be a BOON for the adult toys industry... 5 minutes to 30 minutes of pulsing plasma....
Call it "PlasMastics"....
Then again, it could be useful on public transit, too. A seat sensor would know when someone stood up, ostensibly leaving the seat. Then deodorizers and "plasmatizers" could sanitize seats vacated by some of the most mobile and formidable germs/bac(k)teria (If V'ger had a say in it, hehehehe) that get to a seat by way of expelled vapor(s) and perspiration.
For certain situations, like MedEvac, this might be useful in a sort of sleeping bag enclosure for non-bleeding persons (or pets?) in transport to medical facilities. Just zip up the person and plug the bag in to the Ambulance. Don't know if this would cause any brownouts if plugged in en mass...
Plasma bibs for drooling adults, anyone?
Of course, these sold in the hundreds of millions could spell doom for the atmosphere...
I just geeked out, thinking of having Decontamination chambers in the lobbies of hospitals. Kind of like when they made people wash their feet and tires when leaving or entering farms when they were scared of avian flu.
Think of it, hospitals, schools, airports.. any high concentrations of germs/bacteria, bathe people in these beams of ions as they walk through entrances... Wouldn't kill things inside the people, but I wonder how effective that would be.
Also the image of the nurse scouring the hospital room with her plasma-power torch is very amusing to me.
The problem is we should be using LESS anti-bacterial not making more ways to kill them.
The human immune system is based on exposure to this kind of thing, ever since anti-bacterial cleaners, ever more effective dust removal and the progressive move away from outdoor activities (playing in the dirt) kids have started to develop more and more allergies and have started developing other similar ailments all because their immune system didn't get the jump-start it needed when they were babies.
Erm, the vast majority of our medical knowledge? You don't just have immunity to bacteria, it is something that develops through 'practice' like more obvious things such as coordination and balance. When the immune system works out how to beat a virus, traces of the immune response remain dormant within you after fighting it off. Then if your body is faced with a new infection, any of your existing antibodies that are effective are called into action.
The net effect is you can be exposed to some agent that your system already knows how to beat and not get sick. Vaccination works this way, it was discovered way back when that people who had beaten the cowpox were immune to the deadly smallpox.
"The plasma gun or "flashlight" requires just a 5V battery to..." of course volts are neither a unit of energy or power so this statement is useless for judging the (electrical) efficency of this method. Since it is mentioned that it is handheld and cheap I must asssume the power requirements are fairly low though. All in all I don't guess I had anything of consequence to say.
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