There is new hope for patients with chronic, poorly healing wounds: cold plasma destroys bacteria and stimulates the body’s self-healing powers. Scientists from Greifswald in Germany have developed a new wound dressing based on WACKER silicones that creates high-energy gas directly on the damaged skin.
A blue gas shimmers over damaged skin – with an unusual effect. It causes even chronic wounds to close up within just a few weeks. “Cold plasma can heal,” says Dr. Carsten Mahrenholz, a chemist at the Leibniz Institute for Plasma Science and Technology (INP) in Greifswald and one of the founders of the startup company Coldplasmatech. This cold plasma forms, for example, when a gas passes through strong electric fields – the electrons are dissociated from the molecules and the gas becomes electrically conductive and glows blue.
“Among other things, plasma emits ions, UV radiation and radicals – a mixture of different active substances,” explains Mahrenholz. The Greifswald scientists’ research showed that cold plasma can efficiently kill bacteria. It even effectively combats dreaded antibiotic-resistant hospital pathogens. It acts by purely physical processes, attacking the microbes’ cell membranes, among other targets. This involves several unspecified chemical reactions. Their characteristics prevent the pathogenic organisms from building up resistance in the first place – which eventually is the case with targeted antibiotics.
Everyday Natural Phenomenon
In principle, plasma is an everyday natural phenomenon, a fourth state of matter after solids, liquids and gases. Further heating completely or partly dissociates free charge carriers such as ions and electrons in the gaseous particle mixture, which remains conductive yet outwardly electrically neutral. For example, the sun, lightning and northern lights all exhibit plasma properties.
For the past two decades, scientists at the Greifswald INP have been conducting research on a plasma state that – unlike the sun or lightning – is not scorching-hot, but cool. Furthermore, a project group headed by institute director Prof. Klaus-Dieter Weltmann has been working since 2005 on the development of cold plasma sources for wound care. As part of this research, the scientists intensively studied the effect of a number of spot emitters and larger-area prototypes on living cells. In 2013, a spot source – the plasma pen, which is the size of a fountain pen – obtained approval as a medical product. In addition, studies were started on large-surface plasmas that will allow for more effective treatment of large wounds.