A 3D-printed fence-surface plasma source for skin treatment and its potential for personalized medical application

A 3D-printed fence-surface electrode that has the potential for personalized medical application is fabricated in this study. The framework of the 3D-printed fence electrode could be any shape to fit the outline of the target. Here, the fence electrode with an area of 50 × 50 mm is made as an example to study the discharge characteristic and the affecting factors (number of bars and the curvature of the electrode). The results show that more bars of the fence electrode with the same area will have a larger discharge current and a more uniform glowing area, which is consistent with the numerical results. When introducing the human load, it will not affect the original discharge between the fence and the ground electrodes but will add discharging channels between the fence electrode and the human load when the load contacts the fence electrode. In the worst case, the maximum root-mean-square of the discharge current flowing through the human model is 5.9 mA, which is still lower than the safety thresholds. The highest temperature rise on the surface of the fence electrode is 35.226.55 °C at the condition of 15 bars for 7 kV, 3 min running. It needs a 60 s treatment for Escherichia coli and Staphylococcus aureus to get a sterilization rate of 99.99% while it needs about 180 s treatment for Pseudomonas aeruginosa to get the same rate. Finally, the procedure for designing a personalized fence-surface plasma source is illustrated and the electrodes used to fit the calf and heel are made. The discharge of the personalized fence-electrode is stable and could be used in personalized plasma medicine in the future.