The EIS-platform makes it possible to conduct measurements based on electrical impedance spectroscopy. With this method, you can retrieve quantitative characteristic information from biological systems such as cell size and type discrimination. Without the need to label them.
Commercial applications exist, e.g. EIS is used for bacterial, pollen and blood cell counting.
Together with Fluigent SA and Zurich instruments we developed an electrical impedance spectroscopy platform that uses both electrical and optical detection. This system can handle a fast throughput and can conduct a multiple parameter analysis in one run. Another advantage is that due to reference electrodes in the chip, a more stable signal can be obtained compared to traditional Coulter counter devices.
The electrical impedance spectroscopy chip
The electrical impedance spectroscopy chip is designed in such a way that it aligns cells, beads or particles before passing through a sensing region. The straight through channel is 28µm deep and 30µm wide, making it suitable for several counting and analyses related applications. There are two sets of double electrodes, with planar separation of 20µm and 28µm depth separation. This type of chip was used for several experiments with 3µm and 5µm beads.