Aarhus Universitets segl

SAC Seminar - Jan-Wilm Lackmann: From Space to Skin – Cold Technical Plasmas for Life Science Applications

Oplysninger om arrangementet

Tidspunkt

Tirsdag 16. maj 2017,  kl. 10:15 - 11:00

Sted

1540-116


Plasma, the forth state of matter, describes an ionized or partially ionized gas (mixture) created by introducing additional energy into gas by various means. About 95 % of visible matter in the universe is believed to exist in the plasma state and typical examples for natural occurring plasmas are lightning bolts, the aurora borealis, and stars. Cold technical plasmas are a relatively recent invention allowing for the generation of technical plasmas at relatively low temperatures. Such plasmas are perfectly suited to treat heat-sensitive targets, such as composite materials used in implants and medical devices, plastics, and patients. Typical plasma processes conduct at low-pressure conditions (below 10 Pa), which in turn allows for the generation of large plasma volumes. These setups are used to sterilize medical equipment and investigations show high inactivation efficacies for all tested microorganisms. Standardized spore samples are quickly inactivated with the whole process concluded in the range of seconds. However, low-pressure setups are rather limited for applications with patients. Here, cold atmospheric-pressure plasmas are under investigation to enhance wound healing, cell proliferation. and cancer treatment. In contrast to low-pressure setups, these sources are small with a plasma volume of 1 mm3 or less. In Germany, three plasma sources are accredited for medical use and clinical studies are well under way with promising interim results.

However, the biochemical background of observed influence on spores, vegetative cells, and tissue is only poorly understood. While UV and VUV radiation is discussed as the major player under low-pressure conditions, the mechanism of action under atmospheric conditions seems to be correlated to the generation of various reactive species. As these species interact with each other both in the plasma volume as well as in the water phase present in or around all living organisms, the investigation of reaction pathways is rather challenging. Molecular biology allows monitoring the impact of plasma treatment on various biological probes, model organisms or cell culture systems on a molecular level. Understanding which chemical reactions are triggered by plasma treatment and what damage is introduced to cell components enables the optimization of plasma processes for the various applications, which often have significantly different aims. Spectroscopic and mass spectrometric methods together with molecular dynamics simulations have proven to offer great assistance to understand basic chemical modifications occurring at biological model substrates. Reporter gene studies and mutant collection screening allow investigations of the impact of plasma treatment on bacteria in vivo.