Measurement of reactive species density in the battery-operated, handheld room temperature atmospheric plasma jet for biomedical applications

Room temperature atmospheric pressure plasma jets (RTAPP-Js) have widespread biomedical and health care applications in pathogen inactivation, wound healing, blood coagulation, and interventional oncology, to mention just a few. The overwhelming majority of the existing RTAPP-Js rely on external power (e.g., generators or wall power) and gas feed (e.g., He or Ar gas) supply. This limits their utility in mobile handheld devices for point-of-care applications, e.g., in natural disaster rescue and military combat operations, treatments in remote locations, etc. Moreover, treatment efficacy of such devices should be comparable or superior to current equipment. Recently, Pei et al. have developed a handheld RTAPP-Js (named “Plasma Flashlight”) powered by a 12 V DC battery¹. The plasma source does not rely on any external power or feedstock gas supplies. In this report, we quantitative measured the O₃ density of the Plasma Flashlight by absorption spectroscopy which was performed with a standard mercury lamp. Atom O and OH radicals that play a crucial role in the inactivation process were measured using the laser-induced fluorescence (LIF) technology. The distribution of Atom O and OH radicals in the plasma plum was also studied.