Effects of OH Radical Density from Atmospheric Plasma to Induce Cell Death in Lung Cancer and Normal Cells

Atmospheric plasma's electron temperature is less than thermal plasma, so it is useful at bio experiment. We have investigated the optical emission spectroscopy (OES) lines by spectrometer during Atmospheric plasma bombardment onto the PBS surface by using an Ar gas flow. Also we have measured the OH radical density inside the solution induced by the Atmospheric plasma bombardment. OH radical species are appeared at 308 nm and 309 nm. Densities of OH radical species has been found to be significantly decreased versus depth of the solution from 2 mm to 6 mm. OH radical density inside the PBS is measured to be about $1.87{\times}1016cm-3$ downstream at 2 mm from the surface under optimized Ar gas flow of 200 sccm in Atmospheric plasma. Also we have investigated cell viability of lung cancer and normal cell after Atmospheric plasma treatment for fixed exposure time in 60 seconds, but different depths. We used SEM, we observed change of cell morphorogy, did experiment about FDA & PI Staining method. It is found that there is selectivity between the lung cancer and lung normal cell, in which cancer cell definitely has higher cell death ratio more than normal cell. We have investigated change of bond structure in FT-IR spectroscopy, the following peaks were observed: and intense O-H peak at 3422 cm-1 and at 2925 cm-1 corresponds to C-H stretch vibrations of methylene group.