There is significant optimism that cold atmospheric (ionised gas) plasma could play a role in the treatment of life-threatening diseases, such as non-healing chronic wounds and cancers. The medical benefits from plasma are thought to arise from the reactive oxygen and nitrogen species (RONS) generated by plasma upon interaction with air and liquids. However, it is unclear what RONS are delivered by plasma into tissue fluid and tissue, and their rate of delivery. This knowledge is needed to develop safe and effective plasma therapies.

In this investigation, a simple approach was proposed to monitor the dynamic changes in the concentrations of RONS and dissolved oxygen within tissue-like fluid and tissue during plasma treatment. A plasma “jet” device was shown to non-invasively transport RONS and oxygen deep within tissue (to millimetre depths). However, tissue fluid directly treated with the plasma jet was deoxygenated due to the gas flow purging oxygen out of the fluid.

Monitoring and controlling the plasma delivery of both RONS and oxygen into tissue fluid and tissue is necessary to avoid hypoxia in open wound treatment, to achieve targeted destruction of cancerous cells within solid tumours and to oxygenate oxygen-starved tissue to stimulate tissue regeneration.

J.-S. Oh, E. J. Szili, N. Gaur, S.-H. Hong, H. Furuta, H. Kurita, A. Mizuno, A. Hatta and R. D. Short, How to assess the plasma delivery of RONS into tissue fluid and tissue, J. Phys. D 49, 304005 (2016)