Optical and Structural Properties of Plasma-Treated T98G Brain Tumor Cells

Abstract

We studied the effect of plasma treatment on the optical, structural and biological properties of T98G brain tumor cells. Treatment with dielectric-barrier-discharge (DBD) plasma decreased the viability of T98G cells by modifying and/or destroying cellular proteins with the generated reactive oxygen species, as confirmed by circular dichroism and fluorescence spectroscopic analysis. The DBD plasma in liquid produces various reactive oxygen species (hydroxyl radicals, superoxide anions, and hydrogen peroxide), and the plasma-treated samples exhibit changes in the optical and structural properties. The presence of hydroxyl radicals and superoxide anions in the plasma-treated T98G cells was investigated by measuring the fluorescence signals of T98G cells stained with oxyradical-sensitive fluorescence probes: 3'-(p-hydroxyphenyl) fluorescein, dihydroethidium, and 2',7'-dichlorodihydrofluorescein diacetate. The biological and optical properties of T98G cells treated with an oxidant or antioxidant were compared with those of plasma-treated T98G cells. These results showed that DBD plasma treatment could induce oxidative damage and cell death in T98G cells.