In order to determine the limits of the biologically safe maximum allowable levels of pulsed terahertz (THz) radiation, a prototype of apparatus has been developed for the irradiation of cell cultures immersed in a liquid medium with broad-band THz radiation in the 0.05–1.2 THz frequency range. The action of THz radiation on the functional activity of the cells of a number of biological cultures, including mouse thymocytes and splenocytes, has been investigated. This was evaluated by means of flow-through cytometry, using fluorescence-intensity analysis of DNA-binding stains. It is shown that THz radiation with a mean power density of up to 10 μW/cm<sup>2</sup> and a time of action of 1 min has no effect on the variation of the functional activity of the cells. No statistically reliable variations were detected in the relationship of living cells and cells at different stages of apoptosis or in the distribution of cells over the phases of the cellular cycle. It is concluded that THz radiation with such characteristics can be used for medical spectroscopy.
© 2014 Optical Society of AmericaPDF Article