A novel live cell imaging method with sub-cellular resolution for cell-based assays

A lightweight imaging method based on electrolyte-insulator-semiconductor (EIS) structure was developed to analyze single cells. Cells were cultured on the EIS structure surface, and the impedance of this cell-based biosensor was measured by two-electrode electrochemical system. For the field-effect and internal photoelectric effect of semiconductor and the electric insulativity of living cell, difference impedance was detected when a scanning laser irradiated at the cell-free and cell-on area respectively. Thus, an image of cell distribution and adhesion could be obtained by calculating impedance for each scanning point. The results of the experiment showed that the spatial resolution of the proposed imaging method could reach to 5 µm, and the sensitivity was high, which indicate that it has great potential to be used in various cell-based assays, such as cytotoxicity detection, drug evaluation and cancer research.