Photoelectric behavior of mammalian cells and its bioanalytical applications

In this paper, the photoelectric behavior of mammalian cells is first reported by using ITO (a transparent electrode of indium-tin oxide coated borosilicate) technology. Attached mammalian cells can easily grow on the transparent electrode in a culture flask with general culture medium. This integration of the conductor glass with a layer of mammalian cells and photoelectric-current-measuring system forms a cytosensor when the transparent electrode is mounted into the light path. The attached mammalian cells responds with a negative photoelectric current pulse to white light (200-800 nm). The negative characteristic of the photoelectric current shows electron flow from living cells to the conductor glass. We also found that the fluctuations of the photoelectric current were determined by the coordination of some cell functions. The influence of cell viability, pH and light intensity on the photoelectric behavior is studied. We found that the photoelectric current of tumor cells is higher than that of normal cells, and the photoelectric current of mammalian cells is related to the viability of the cells. (C) 1998 Elsevier Science S.A. All rights reserved.