Stretchable Impedance Spectroscopy Sensor for Mammalian Cells Impedance Measurements

In this paper, an impedance spectroscopy biosensor fabricated on a stretchable substrate has been investigated. A thin stretchable membrane integrated with an impedance biosensor tolerated cyclic strain without cracking. The electric cell-substrate impedance spectroscopy (ECIS) technique has been used to monitor the impedance of the membrane of bovine aortic endothelial cells (BAEC). Integrating mechanical stretching and ECIS sensing onto a single platform requires biocompatible, highly flexible, and reversibly stretchable (elastic) materials for device fabrication. In addition, the interfacial impedance of electrode material to electrolyte should be small to improve the sensitivity of the impedance measurements. In this research, the biocompatible and stretchable membrane was fabricated from polydimethylsiloxane (PDMS), and the ECIS sensor was fabricated on pre-stretched PDMS membrane using sputtering microfabrication and pattern-transferring processes. The stretchable membrane, integrated with the ECIS sensor, can be used to simulate the dynamic environment of organisms and enable the analysis of the cell activity in vitro.