Download Modeling Atmospheric Pressure Plasmas for Biomedical Applications David B. Graves U.C. Berkeley

Modeling Atmospheric Pressure Plasmas for Biomedical Applications
David B. Graves
U.C. Berkeley
Berkeley, CA 94720
The use of cold, atmospheric pressure plasmas for biomedical treatments is an exciting new
application in low temperature plasma processing and gaseous electronics. Plasmas have been
used for many years to treat metal and polymer surfaces for biocompatibility. A variety of low
temperature plasma devices have also been used in surgery, and more recently in plasma-based
sterilization. The newest developments for low temperature plasma medical applications concern
areas like wound healing and direct treatment of diseased tissue. In this talk, I will present results
from modeling the ‘plasma needle,’ an atmospheric pressure plasma configuration that has been
explored by several groups around the world. The biomedical efficacy of the plasma needle, as
well as similar devices, has been demonstrated but the mechanisms of cell and tissue modification
or bacterial destruction are only just being established. One motivation for developing models is
to help interpret experiments and evaluate postulated mechanisms. The model reveals important
elements of the plasma needle sustaining mechanisms and operating modes. The model has
provided basic insights into patterns of light emission, and these have been compared with
experiment. However, the extraordinary complexity of plasma-tissue interactions represents a
long-term challenge for this burgeoning field. I also comment on the challenges of developing
fundamental data for plasma-biomaterial interactions and contrast this challenge with approaches
taken, for example, in developing comparable data for plasma-semiconductor surface interactions.
Although the conditions and applications are often significantly different, plasma-surface studies
of the past several decades in semiconductor materials processing offer some hints about what
might be important in this new field.