The term “plasma medicine” indicates a new field of research, which studies the possible uses of plasma, which is a gas that is partially ionized through the application of an electric field, at low temperature and at atmospheric pressure, for therapeutic purposes.Emilio Martines, head of the plasma medicine group at Consorzio RFX
About ten years ago, Consorzio RFX began to develop a line of research on plasma medicine.
Chemical reactions take place inside the plasma involving the atoms present in it. This gives rise to the formation of particular chemical species, which can interact with the cells of the human body or with the pathogens (bacteria, fungi, etc.) which are at the origin of some diseases.
Interaction with pathogens leads to their death, making plasma interesting for its disinfectant properties. But it can also “induce” cells to assume certain behaviors, ranging from proliferation to migration to “cell suicide” (apoptosis).
The disinfectant properties of plasma are useful in various areas. The first application that was developed by the Padua group is the use of plasma for the treatment of ocular surface infections (keratitis). But other applications are also being studied, such as accelerating the healing of wounds and sores or treatment in the oncology field for killing cancer cells. Experimenting on thin layers of cells in the laboratory, we have the first positive results of selective killing of cancer cells.
Bacterial and viral cells have a lower resistance than eukaryotic cells, those that make up our body, to reactive chemical species, ROS, produced by low temperature plasma sources operating at atmospheric pressure. Consequently, the bacterial cells will die after a short exposure to the gases produced by the source, unlike the cells of the human body which will remain unharmed, thus having the disinfectant effect. Having alternative disinfection methods can be very important especially in cases of antibiotic resistance or even just as an alternative to a topical antibiotic treatment to avoid excessive use.
Cancer cells are subject to very fast growth, this contributes to making them more sensitive to reactive species produced by cold plasma sources. In the same way as bacteria, therefore, tumors will undergo cell death of non-oncogenic eukaryotic cells after exposure to gases from plasma sources. This developing technology would therefore allow to selectively target the diseased cells while leaving the healthy ones unharmed. Currently, however, experiments in this sense have only been carried out in the laboratory on cell lines, i.e. on a single layer of cells grown in the laboratory.
This line of research has led to the production of two patents: