SEP 13, 2017 06:00 AM PDT

Plasma Medicine - Research Sheds Light On The Cause of Turbulence

The low-temperature atmospheric pressure plasma jet in action. Credit: Amanda Lietz

Plasma, the fourth state of matter, is an ionized gas containing positive and negative ions or electrons. Nowadays various types of plasmas are used in different applications, from welding and vehicle exhaust cleanup to fighter jet engines and fusion reactors.

Plasma medicine is an emerging field that explores the potential of low temperature (upper limit of 50 °C) atmospheric plasma in clinical practice. This specific plasma uses helium as the gas source and produces chemically reactive species such as hydroxyl and nitric-oxide molecules. It can be useful in biomedical applications such as sterilization, disinfection and cancer therapy because the radicals can tear into the cellular structure of bacteria and cancer tissues. But there is often turbulence within the plasma jets - variance in flow direction and velocity. Ideally, in an application such as sterilization or therapy, a steady flow of plasma can guarantee predictable amount of radicals for the needed application. But turbulence in plasma would fail consistency.

For a long time, the cause of the turbulence remains unknown. Now, according to the new research published on the journal Applied Physics Letters, it could be caused by heat-induced sound waves generated at the plasma electrodes. By simulating the plasma jets, they discovered that the localized heating at the tip of the electrode (whose electric field ionizes gas) occurs on the time scale of the voltage pulse from 10 to 100 nano-second. The heat intensified the movement of gas molecules and created vibration (a propagating sound wave) which travels along with the stream. When the wave front reached the boundary of the electrode, where the plasma hit the air, it disrupted the plasma layer and caused turbulence.

The researchers hope that by figuring out how and where the turbulence occurs, they may be able to develop methods to control it and create a more consistent plasma-delivering device for medical applications. “Now that this phenomenon is relatively understood, researchers can enhance or dampen this effect, depending on what's best for the patient. Ultimately, this new analysis can lead to an approved and reliable treatment”, said Dr. Mark J. Kushner from the University of Michigan and the supervising author of the report.

Source: phys.org/Applied Physics Letters

About the Author
  • Graduated with a bachelor degree in Pharmaceutical Science and a master degree in neuropharmacology, Daniel is a radiopharmaceutical and radiobiology expert based in Ottawa, Canada. With years of experience in biomedical R&D, Daniel is very into writing. He is constantly fascinated by what's happening in the world of science. He hopes to capture the public's interest and promote scientific literacy with his trending news articles. The recurring topics in his Chemistry & Physics trending news section include alternative energy, material science, theoretical physics, medical imaging, and green chemistry.
You May Also Like
JAN 17, 2020
Chemistry & Physics
JAN 17, 2020
What do a Wing Nut and a Tennis Racket Have in Common?
In 1985 during a mission to rescue the space station Salyut-7, Soviet astronaut Vladimir Dzhanibekov observed something rather strange. A free-flowing wing...
JAN 17, 2020
Technology
JAN 17, 2020
Molecular Eraser Increases Data Storage Efficiency
Researchers at the University of Alberta in Canada have explained a hydrogen-related novel method that takes advantage of a natural physical phenomenon to ...
JAN 17, 2020
Drug Discovery & Development
JAN 17, 2020
MagLev: Telling Drugs Apart
Likely, a suspicious powder will be composed of illicit drugs but nothing is certain until confirmation. To do so, analysis must be quick and efficient and...
JAN 17, 2020
Chemistry & Physics
JAN 17, 2020
The Science Behind Christmas
The holiday season is upon us, and to wrap-up the year and get you into the holiday spirit, we are dedicating the last infographic to Christmas. After all, what's a better way to celebrate...
JAN 17, 2020
Chemistry & Physics
JAN 17, 2020
Century-old Bretherton's Bubble Problem Solved
Some of the most common phenomena in life also hide puzzling mysteries.  When you pour water into a glass, many air bubbles would often appear. Becaus...
JAN 17, 2020
Chemistry & Physics
JAN 17, 2020
High-speed 3D Printer to Revolutionize Manufacturing
Two significant hurdles in front of the fast expansion of three-dimensional (3D) printers are speed and scale.  In a recently published study, a team...
Loading Comments...