Generation and measurement of low-temperature plasma for cancer therapy: a historical review

Abstract

This review provides a description of the historical background of the development of biological applications of low-temperature plasmas. The generation of plasma, methods and devices, plasma sources, and measurements of plasma properties, such as electron dynamics and chemical species generation in both gaseous and aqueous phases, were assessed. Currently, direct irradiation methods for plasma discharges contacting biological surfaces, such as the skin and teeth, are related to plasma biological interactions. Indirect methods using plasma-treated liquids are based on plasma–liquid interactions. The use of these two methods is rapidly increasing in preclinical studies and cancer therapy. The authors address the prospects for further developments in cancer therapeutic applications by understanding the interactions between the plasma and living organisms.

Keywords:

• Low-temperature plasma (LTP)
• reactive oxygen and nitrogen species (RONS)

Acknowledgments

The authors would like to thank professors Dr. Fumitaka Kikkawa, Dr. Keiji Imoto, and Dr. Akio Komori for encouraging this work; and Professor Dr. Masafumi Ito and the Hori-Ishikawa laboratory of Nagoya University for fruitful discussion and technical assistances.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This is supported in part by KAKENHI Grants-in-Aid (nos. 19H05462, 17H02805, 20H00142, and 21H04451) from JSPS and by the Center for Low Temperature Plasma Science, Nagoya University.