Novel surface dielectric barrier discharge for basic research in plasma medicine

In the past, it has been shown that with an electrode array described by Oehmigen et al. several basic insights into mechanisms of plasma-liquid and plasma-cell interactions can be achieved.^1-5 Unfortunately, this laboratory-designed experimental set up has some disadvantages. To optimize the daily laboratory use, a new surface dielectric barrier discharge arrangement was developed to get a plasma device which ensures a more flexible and durable application during biomedical experiments, whereby, permanently reproducible results can be achieved. To get the desired qualifications the dielectric material was replaced by ceramic material (Al₂O₃) and the embedded high-voltage (HV) electrode was covered with a permanent glass layer to protect the HV-electrode against sputtering processes and to keep the electrode robust and durable. The complete electrode array is embedded into a gas-tight chamber to get a constant and controllable environment during the experiments. Moreover, the power supply was replaced to obtain more flexible discharge parameters. Along with all these adjustments the driving parameters for the discharge had to be adapted. In this study, the influence of the mentioned innovations including the impact of the feeding gas composition, the generation of reactive species within the liquid phase, and the biological effects were assessed. It is demonstrated that even with varying technical parameters of the plasma source comparable biological effects can be realized. This underlines the necessity of a comprehensive, comparative, and structured characterization of plasma sources for biomedical applications which includes both technical and biological performance data.