Plasma medicine is a new interdisciplinary field of research that includes physics, chemistry, biology, and medicine.
Currently, plasma-chemical technologies are of great interest for modern medicine, biology and biotechnology and are promising methods for solving a number of urgent problems: sterilization, stimulation of cell regeneration, treatment of inflammatory diseases, treatment of wounds, etc. The main type of plasma used to solve biomedical problems is is the plasma of gas discharges ("cold plasma").
The Plasma Health project, promoted by IPLASMA, is aimed at large-scale implementation of breakthrough plasma medicine technologies in such areas as dermatology, surgery, oncology, dentistry, gynecology, otorhinolaryngology, etc.
When using "cold plasma" for medical purposes, a biological object is immediately affected by a whole complex of chemically active particles, photons, as well as charged particles and an electric field.
Each of the above components can have a bactericidal effect or lead to stimulation of eukaryotic cells; reactive oxygen and nitrogen particles play an important role in all types of plasma interactions with biological objects:
The synergism of the action of the components of the plasma torch is a feature of cold plasma, which is important for its medical use. Each component is present in relatively low concentrations and is non-toxic, but the interaction of several such effects can enhance the effect and hit the same target. The most promising candidates for synergistic action with biologically important consequences are ROS and RNS, they play an important role in the processes inactivation of bacteria under the influence of low-temperature cold plasma.
Conducting numerous experiments in vivo proves that cold plasma has rather valuable properties with great potential for use in medicine - bactericidal, fungicidal and antiviral effects, destroys biofilms, affects on blood clotting, the immune system, on proliferation and apoptosis of cancer cells.
As a result of the interaction of cold plasma with living systems, a number of active agents are formed: neutral gas, charged particles, excited atoms and molecules, active molecules (NO, O3, OH-, O2-, H2O2), electric field, heat, ultraviolet radiation. Of all the possible factors generated by plasma in biological. The effects are mainly involved in long-lived radicals and nitrogen monoxide (NO), they directly interact with biological substrates.
Plasma can exist in many forms and can be created in many different ways. In many technological applications, plasma exists at low gas pressures. It is important to distinguish between thermal and nonthermal plasma.
Lightning is an example of atmospheric pressure thermal plasma. In a non-thermal plasma, the cooling of ions and uncharged molecules is more efficient than the energy transfer from electrons, and the plasma maintains a low temperature (25-40 ° C); therefore, non-thermal plasma is also called non-equilibrium plasma.
We concentrate mainly on new non-thermal effects and on possible non-thermal mechanisms of interaction between plasma and living organisms. Treatment when using non-thermal plasma effects in medicine divided into two categories: direct plasma treatment and indirect plasma treatment. In direct plasma treatment, living tissue (or organ) plays the role of one of electrodes between which plasma is formed.
Disadvantages - some current can flow through the tissue (weak conduction current, displacement current, or both). Difficulty handling non-planar surfaces.
In indirect treatment, active elements (electrons, positively charged ions, radicals, etc.) are delivered to the surface of a biological object through the flow of plasma-forming gas and through the plasma region. The ability to handle complex curved surfaces.
Disadvantages - relatively small cultivated area; high temperature of the plasma flow; expensive plasma sources.
In addition, under optimal conditions, plasma is able to selectively affect the affected skin areas, destroying pathogenic prokaryotic organisms. Its disinfecting effect is based on the ability of ions and electrons to penetrate the cell membrane and destroy the unprotected structure of bacteria. More protected eukaryotes are able to counteract the plasma attack longer - it is this time difference that gives doctors the ability to destroy bacteria without harming the cells of the body. Cold atmospheric pressure plasma is safe and can be effectively applied directly to the human body.
To obtain plasma, it is necessary to deliver energy to the gas in some way, so that the rearrangement of the electronic structures of molecules and atoms, as well as the creation of excited states and ions, can occur. This energy can be electrical, thermal, electromagnetic energy. For most cases, electrical energy is used. In this case, the bulk of the energy is transferred to electrons, which interact with neutral particles through elastic and inelastic interactions. Elastic changes the kinetic energy of neutral particles in the direction of increasing, and inelastic leads to ionization, and also the occurrence of excited states (provided that a sufficient amount of energy is transferred). The frequency of the exciting field is also very important, because it determines how the charged particles will move. If we are dealing with low frequencies, then charged particles keep pace with field changes, and with increasing frequency ions, due to their large mass, begin to react already to the average value electric field.
One of the fundamental methods of obtaining plasma was spark discharge. At atmospheric pressure, gases contain almost no charged particles; in order to initiate a breakdown, it is first necessary to ionize the gas.
This goal can be served by only one electron, which, accelerating in an electric field, can knock electrons out of neutral molecules and atoms, and since after knocking out there are already 2 electrons, the process begins to actively spread throughout the volume of the gas. It should be remembered that along with the ionization process, there is also a recombination process. Several types of electrical discharges are used to ionize gas and obtain cold plasma:
Barrier and microwave discharges are most commonly used in existing cold plasma devices used for medical purposes.
Microwave discharge - gas ionization by a powerful microwave electric field, operating frequencies of the order of 2-5 GHz (GHz). High frequency and high voltage discharge 1-13MHz (MHz).
Barrier discharge - discharge between two electrodes separated by a layer dielectric.
This type of discharge is used in 70% of devices generating cold plasma. As a plasma-forming gas, noble gases such as helium and argon are currently used in medical devices for cold plasma due to their much lower energy consumption for their ionization.
IPLASMA has developed a fundamentally new technology for producing cold plasma of a nanosecond discharge, which makes it possible to eliminate the disadvantages of the indirect method of exposure to cold plasma that are present today.
Plasma Health technology has an undeniable priority on the territory of the Russian Federation. IPLASMA company, based on the Plasma Health technology, is developing a line of medical devices for cold plasma treatment in various fields of medicine and cosmetology.