LAUSR

In this work, we report that the effect of bioactive constituent on living glioma cells can be evaluated using terahertz time-domain attenuated total reflection (THz TD-ATR) spectroscopy in a label-free, non-invasive, and fast manner. The measured THz absorption coefficient of human glioma cells (U87) in cell culture media increases with ginsenoside Rg3 (G-Rg3) concentration in the range from 0 to 50 µM, which can be interpreted as that G-Rg3 deteriorated the cellular state. This is supported either by the cell growth inhibition rate measured using a conventional cell viability test kit or by the cellular morphological changes observed with fluorescence microscopy. These results verify the effectiveness of using the THz TD-ATR spectroscopy to detect the action of G-Rg3 on glioma cells in vitro. The demonstrated technique thus opens a new route to assessing the efficacy of bioactive constituents on cells or helping screen cell-targeted drugs.