Response of Biological Cell Exposed on Burst RF Fields

Burst RF fields (BRFFs) were applied to Chinese Hamster Ovary (CHO) cells, and the cell response to the BRFF of two different frequencies, 20 kHz and 50 MHz, was investigated by means of the fluorescent microscopy. The field strength and duration of the BRFF were fixed at 1 kV/cm, and 100 mus, respectively. Cells were placed in a 100 mum-gap electrode plated on the slide glass for a microscopy. Acridine orange (AO), which mainly reacts to DNA, was used as the fluorescent dye. From the experiment, the BRFF of 20 kHz initiates the increase in the permeability of cell membrane. In contrast, the BRFF of 50 MHz does not act on cell membrane but causes degeneration of DNA or RNA. We have experimentally demonstrated that the burst RF fields with only a small electric field of 1 kV/cm cause not only membrane reaction but also intracellular effects.