title: Method to quantify the effect of passivation layer in bio-impedance sensors.
abstract: This paper investigates the effect of the passivation layer in a bio-impedance sensor. A sensor with 20 sensing sites has been designed, fabricated using a simple two mask process and tested. We have cultured in-vivo MDA-MB231 mammary cells and recorded the impedance from 1kHz to 1MHz. Processing the recorded data brings to light the drawback of the passivation layer which results in a drop in sensitivity of 13%. Simulation results based on parameters extracted from measurements re-affirm the drop in sensitivity. Thus, the passivation layer needs to be provided a special consideration in future design of the sensor as it can modify the response of the sensor.
authors: The Bradley Department of Electrical and Computer Engineering, Virginia Tech, Blacksburg, 24060, USA. snsnair@vt.edu
authors: Shree
authors: S
authors: Narayanan
authors: Mehdi
authors: M
authors: Nikkhah
authors: Jeannine S
authors: JS
authors: Strobl
authors: Masoud
authors: M
authors: Agah
mesh_terms: D000465:Algorithms; D001703:Biophysics; D015374:Biosensing Techniques; D001943:Breast Neoplasms / Q000473:pathology*; D045744:Cell Line, Tumor; D003198:Computer Simulation; D017097:Electric Impedance; D004594:Electrophysiology / Q000379:methods; D004867:Equipment Design; D006801:Humans; D008839:Microelectrodes; D008855:Microscopy, Electron, Scanning / Q000379:methods; D055095:Optics and Photonics; D014159:Transducers