Monitoring of cell growth in vitro using biochips packaged with indium tin oxide sensors

Cell-based biosensors, which treat living cells as sensing elements, are able to detect the functional information of biologically active analytes and also provide quantitative analysis. In general, they maintain living cells and observe the cellular physiological response after subjecting cells to stimulus and verify the presence and the concentration of these stimuli. This paper describes the use of indium tin oxide (ITO) as a bioimpedance sensor. ITO was chosen as the sensor material due to its optical transparency, electrical characteristics and biocompatibility. These features enabled cells to be visualised and cell signalling to be assessed thus enabling real time non-invasive in vitro analysis of the physiological state of biological cells. The developed biochip integrates optical and electronic devices for monitoring cell behaviour and would facilitate long-term measurement of cytotoxicity. It is envisaged that the developed technology together with proprietary assays will address markets including the pharmaceutical industry, environmental monitoring, health care and security/defence sectors.