Transparent Thin Film Transistor Electrode Array for Real-Time Electrical Impedance Spectroscopy of Cell Cultures

We present the usage of an optically transparent Thin Film Transistor (TFT) electrode array to perform arbitrarily spatially confined electrical characterizations of a cell culture. These arrays are a mature technology commonly used in Liquid Crystal Displays, and manufacturable on a scale of up to square meters. Electrical characterization allows one to detect not only changes of concentration of cells in cultures, but also the components and state of the cells in the culture. Unfortunately these characterizations are extremely dependent on the positioning of the cell with respect to the electrode and as such require specialized conditions or trapping mechanisms to garner consistent data. By utilizing a large TFT electrode array we are able to get around this by providing a stochastic aggregate throughout the array that provides consistent metrics for the culture. It has been verified that this device is capable of electrically detecting changes in the living and dead cell populations of yeast (S. Cerevisiae).