Biological and medical application of intense electromagnetic radiation

Kado, Masataka; Katsuki, Sunao*

This paper describes the biological effect of an intense pulsed electric field and electromagnetic radiation that varies by frequency band. A field with less frequency than 1 MHz provides an electrical stress to the plasma membrane, but that with higher frequency is likely to affect the intracellular components. A laser plasma soft X-ray microscope, which is a combination of highly intense laser plasma soft X-ray sources and a contact type soft X-ray microscope, has been developed. The laser plasma soft X-ray microscope captures an X-ray image of live hydrated biological cells with 80-nm spatial resolution in a 600-ps time duration. Cellular organelles such as chromatin, mitochondria and actin filaments have been observed with the laser plasma soft X-ray microscope in combination with a fluorescence microscope to identify cellular organelles. We also observed such life phenomenon as an apoptotic process and detailed structural deformation.