These plasma-generated active species are useful for several bio-medical applications such as sterilization of implants and surgical instruments as well as modifying biomaterial surface properties.
Dielectric-barrier discharges are a type of plasma source that limits the current using a dielectric that covers one or both electrodes.
[6] The performance characteristics of these actuators can be tuned and optimised by strategically manipulating the electrode's encapsulation and placement throughout the dielectric layer.
In order to use DC and 50/60 Hz power sources investigators developed the Resistive Barrier Discharge (RBD).
[12] The gas used is usually helium or argon, sometimes with a small amount (< 5%) of O2, H2O or N2 mixed in to increase the production of chemically reactive atoms and molecules.
Those that use a dielectric to limit current usually consists of a tube made of quartz or alumina, with a high voltage electrode wrapped around the outside.
Designs that do not use a dielectric to limit the current use a high voltage pin electrode at the center of the quartz tube.
These devices all generate ionization waves that begin inside the jet and propagate out to mix with the ambient air.
In this case, the plasma does not exit the jet, and only the neutral atoms and molecules and photons reach the sample.
Low temperature plasma jets have been used in various biomedical applications ranging from the inactivation of bacteria to the killing of cancer cells.
[23] However, the basic understanding of mechanisms of plasma effects on different components of living systems is in the early beginning.
[36] Though many positive results have been seen in the experiments, it is not clear what the dominant mechanism of action is for any applications in plasma medicine.
The plasma treatment generates reactive oxygen and nitrogen species, which include free radicals.
For example, the uptake of 20 nm gold nanoparticles can be stimulated in cancer cells using non-lethal doses of cold plasma.