The fourth state of matter, plasma, has previously shown its worth in the medical industry, effectively killing bacteria and viruses on the surface of the skin and in water. It is thought that the reactions between plasma and the air surrounding it create a cocktail of reactive species similar to that of our immune system. This reaction ultimately kills off bacteria and viruses, making plasma a highly useful medical approach.
A team of scientists from several leading research institutes in China and Australia has developed a handheld battery-powered plasma flashlight for ridding bacteria from skin and other surfaces. This device is self-contained and operates on a 12-V battery, eliminating the need for an external gas feed or power source. The devices generates a jet of plasma between 20-23°C, a safe temperature as to not harm human skin.
A team of scientists grew thick biofilms of Enterococcus faecalis to test the efficiency of the bacteria-killing plasma flashlight (Shutterstock)
In order to test the prototype of this device, the aforementioned team of scientists, led by Xinpei Lu of the Huazhong University of Science and Technology in China, grew thick biofilms of Enterococcus faecalis. This bacteria is known to infect root canals in the mouth and is highly resistant to both heat and antibiotics. Portions of these samples were kept as controls, while others were subjected to the plasma flashlight for five minutes at a distance of five millimetres. Results of this experiment proved that the plasma not only inactivated the top layer of cells, but penetrated deep into the very bottom of the layers – about 17 cells deep – to eradicate the bacteria. The results of this study can be found published online in the Journal of Physics D: Applied Physics.
The research team behind the plasma flashlight has suggested that the device may cost as little as $100 to manufacture, and may be reduced to an even smaller size. Like all other medical devices, the plasma flashlight will have to go through rigorous clinical testing. But, Professor Kostya Ostrikov of the Plasma Nanoscience Centre Australia, says that besides making it smaller and optimising its efficiency, the plasma flashlight is "pretty much" a commercial device already.
The scientists who developed this device imply that the battery-powered plasma-producing flashlight could be used in the future in ambulance emergency calls, natural disaster sites, military combat operations, and many other instances where treatment is required in emergency situations or remote locations. The device may prove useful in medical relief of those exposed to large amounts of bacteria and viruses resulting from many types of sudden medical disasters. The safety and convenience of using plasma through a handheld, low temperature device in order to kill bacteria will hopefully prove an essential tool for disaster relief in near future.
Shannon Rafferty and Ian Portelli