Handheld plasma flashlight rids skin of notorious pathogens

Handheld plasma flashlight rids skin of notorious pathogens

(PhysOrg.com) -- A group of Chinese and Australian scientists have developed a handheld, battery-powered plasma-producing device that can rid skin of bacteria in an instant.

The device could be used in ambulance emergency calls, natural disaster sites, military combat operations and many other instances where treatment is required in remote locations.

The flashlight, presented today, 5 April, in IOP Publishing's Journal of Physics D: is driven by a 12 V battery and doesn't require any external generator or wall power; it also doesn't require any external gas feed or handling system.

In the experiment, the plasma flashlight effectively inactivated a thick of one of the most antibiotic- and heat-resistant bacteria, Enterococcus faecalis – a bacterium which often infects the root canals during dental treatments.

The biofilms were created by incubating the bacteria for seven days. The biofilms were around 25 micrometres thick and consisted of 17 different layers of bacteria. Each one was treated for five minutes with the plasma flashlight and then analysed to see how much of the bacteria survived.

Results showed that the plasma not only inactivated the top layer of cells, but penetrated deep into the very bottom of the layers to kill the bacteria.

Co-author of the study, Professor Kostya (Ken) Ostrikov, from the Plasma Nanoscience Centre Australia, CSIRO Materials Science and Engineering, said: "The bacteria form thick biofilms, which makes them enormously resistant against inactivation which is extremely difficult to implement. High temperatures are commonly used but they would obviously burn our skin.

"In this study we chose an extreme example to demonstrate that the plasma flashlight can be very effective even at room temperature. For individual , the inactivation time could be just tens of seconds."

Plasma – the fourth state of matter in addition to solids, liquids and gases – has previously shown its worth in the medical industry by effectively killing bacteria and viruses on the surface of the skin and in water.

Although the exact mechanism behind the anti-bacterial effect of plasma is largely unknown, it is thought that reactions between the plasma and the air surrounding it create a cocktail of reactive species that are similar to the ones found in our own immune system.

The researchers ran an analysis to see what species were present in the plasma and found that highly-reactive nitrogen- and oxygen-related species dominated the results. Ultraviolet radiation has also been theorised as a reason behind plasma's success; however, this was shown to be low in the jet created by the plasma flashlight, adding to the safety aspect of the device.

The temperature of the plume of plasma in the experiments was between 20-230C, which is very close to room temperature and therefore prevents any damage to the skin. The device itself is fitted with resistors to stop it heating up and making it safe to touch.

"The device can be easily made and costs less than 100 US dollars to produce. Of course, some miniaturisation and engineering design may be needed to make it more appealing and ready for commercialisation," Ostrikov continued.

The device was created by an international team of researchers from Huazhong University of Science and Technology, CSIRO Materials Science and Engineering, The University of Sydney and the City University of Hong Kong.


Explore further

Plasma-based treatment goes viral

More information: Inactivation of a 25.5 µm Enterococcus faecalis biofilm by a room-temperature, battery-operated, handheld air plasma jet, 2012 J. Phys. D: Appl. Phys. 45 165205. iopscience.iop.org/0022-3727/45/16/165205
Citation: Handheld plasma flashlight rids skin of notorious pathogens (2012, April 4) retrieved 16 July 2019 from https://phys.org/news/2012-04-handheld-plasma-flashlight-skin-notorious.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
0 shares

Feedback to editors

User comments

Apr 04, 2012
I want a plasma toothbrush!

Apr 04, 2012
Can I use this to do the dishes? What about shine my shoes?
Awesome device, looking forward to more plasmonic tech!

Apr 04, 2012
This is huge!

Apr 04, 2012
This exact same findings have already been known by American plasma physicists for years.

Do a search for "Plasma Pen".

It was even seen on Discovery several years ago in much this same concept, in demonstration being used to kill bacteria on the skin without harming the skin.

Apr 04, 2012
This could become a billion-dollar product for preventing teenage acne. Companies need to pounce on this NOW.

Apr 05, 2012
I want a plasma toothbrush!


It needs to be clinically proven first that plasma will not cause mouth cancer. The outer skin is tough and take mild EM radiation.

I doubt the skin cells in the mouth are that tough though.

Apr 05, 2012
This could become a billion-dollar product for preventing teenage acne. Companies need to pounce on this NOW.


What you wrote here, is an idea worthing a billion or more.
-.

Apr 05, 2012
The researchers ran an analysis to see what species were present in the plasma and found that highly-reactive nitrogen- and oxygen-related species dominated the results.

The temperature of the plume of plasma in the experiments was between 20-230C

So basically they are poisoning the bacteria to death. If that's the case, then why do they need a plasma in the first place? Why not just use a compressed bottle of the noxious gas instead?

Also, I have worked with these NOx gases in the past and they are really nasty. You really don't want to be breathing that stuff. Using something like this in a closed area is potentially quite dangerous.

Apr 05, 2012
The researchers ran an analysis to see what species were present in the plasma and found that highly-reactive nitrogen- and oxygen-related species dominated the results.

Species inactivated by the plasma?

Apr 05, 2012
This exact same findings have already been known by American plasma physicists for years. Do a search for "Plasma Pen". It was even seen on Discovery several years ago in much this same concept, in demonstration being used to kill bacteria on the skin without harming the skin.


The creator of that plasma pencil, Mounir Laroussi, is cited by the authors in this paper in the very first paragraph. The improvement made on Loroussi's design is cordless portability.

Apr 05, 2012
"The device could be used in ambulance emergency calls, natural disaster sites, military combat operations and many other instances where treatment is required in remote locations."

Bordellos?

Apr 05, 2012
Species inactivated by the plasma?


'Species' in the chemistry sense, is a term given to atoms/molecules/ions undergoing chemical processes or measurement.

Apr 05, 2012
Axemaster:

The compounds are being produced in nano-scale quantities.

It's possible it may also be ionizing the atoms in the membranes of the bacteria, destroying the cell membrane.

While this could probably cause damage to human tissue if exposed long enough, it's probably worth it. After all, if you don't kill the bacteria, the human tissue is going to be destroyed anyway as the bacteria grows and consumes the tissues.

Most of your tissue in your mouth and skin grows back pretty quickly once you get rid of bacteria, and while teeth don't grow back, you can at least put a full stop to decay.

Apr 05, 2012
This comment has been removed by a moderator.

Apr 05, 2012
I had to look at the date to make sure it wasn't posted April 1st. Sounds really interesting.

Apr 07, 2012
"The temperature of the plume of plasma in the experiments was between 20-230C,"

I think you meant 20-23C ?

Great artic!e!
Love this site!

210
Apr 10, 2012
"The device could be used in ambulance emergency calls, natural disaster sites, military combat operations and many other instances where treatment is required in remote locations."

Bordellos?

Our deadliest STDs are viruses. How do you kill the dead? Can this device do that?

word-

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more