Influence of Plasma Irradiation on Silkworm

摘要

Silkworms have recently been proposed as an animal model for safety testing in basic research. We propose using silkworms for in vivo trials of direct plasma treatment. In this study, the influence of plasma irradiation on silkworms was investigated using a non-thermal atmospheric pressure plasma. Silkworm survival rate decreased with increasing low-frequency voltage and plasma irradiation period. Further investigation of the plasma-generated agents (oxygen related radicals, UV light, and charged particles), revealed that the contribution of charged particles significantly increases silkworm mortality. Non-equilibrium plasmas are characterized by the electrons in the plasma having a higher mean energy than the ions or atoms. This higher energy can produce sufficient active chemical radicals for the high-speed surface processing of materials without causing thermal damage. Recently, non-equilibrium atmospheric pressure plasma has been studied in direct contact with living tissues in order to deactivate pathogens, stop bleeding with no damage to healthy tissue, disinfect wounds and accelerate wound healing,3 and to selectively kill some types of cancer cells.4 However, much research is still required to clarify and minimize the health risks of plasma treatment. In particular, in vivo trials using animal models are essential for predicting the risks of plasma treatment. The use of mammals for experimental models has many associated problems, such as high cost and ethical issues.