Reactive chemical species generated by atmospheric pressure plasma have been shown to selectively kill cancer cells. However, there is currently no established method for delivering these species into the human body. In this study, our goal is to encapsulate these species directly into alginate microcapsules, which are widely used as drug delivery carriers. To accomplish this goal, we developed a micro-surface discharge device that can be seamlessly integrated with a microfluidic system to produce alginate microcapsules. The surface discharge device consists of a silicone tube with a 0.5 mm inner diameter, aluminum tape wrapped around its exterior as a grounded electrode, and a metal needle inserted inside the tube as a high-voltage one, with a gap maintained between them. The device exhibited violet emission, which is attributed to nitrogen excitation, under both atmospheric discharge and discharge with flowing ultrapure water. Additionally, spike-like discharge current waveforms were observed in the electrical signal analyses. These results confirm that the developed micro-surface discharge device can generate plasma.
YOSHIDA et al. (Wed,) studied this question.