Long term in vitro monitoring of polyimide microprobe electrical properties

Author

Nikles, S.A. ; Pellinen, D.S. ; Kitagawa, J. ; Bradley, R.M. ; Kipke, D.R. ; Najafi, Khalil

Author_Institution

Center for Wireless Integrated Microsyst., Michigan Univ., Ann Arbor, MI, USA

Volume

4

fYear

2003

fDate

17-21 Sept. 2003

Firstpage

3340

Abstract

In vitro soak tests lasting over 400 days were performed on polyimide sieve electrodes (PI2611D) using a method that allows in situ measurement of the impedance and relative dielectric constant of polyimide or alternate polymers. It was found that following an initial period of change, both values stabilized after a period of about 100 days. The dielectric constant was measured at 1 kHz and found to increase by 18% over 406 days. A short-term comparison (23 days) between polyimide cured on a hotplate in air versus using an oven with N₂ was also performed. No difference could be seen between the 2 methods.

Keywords

biomedical materials; curing; electric impedance measurement; electric properties; microelectrodes; neurophysiology; permittivity measurement; prosthetics; 1 kHz; 100 to 406 day; 23 days; N₂; dielectric constant; electrical properties; impedance measurement; in vitro monitoring; in vitro soak test; neural probe; polyimide microprobe; polyimide sieve electrodes; Dielectric constant; Dielectric measurements; Electrodes; Impedance measurement; In vitro; Monitoring; Performance evaluation; Polyimides; Polymers; Testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Engineering in Medicine and Biology Society, 2003. Proceedings of the 25th Annual International Conference of the IEEE

ISSN

1094-687X

Print_ISBN

0-7803-7789-3

Type

conf

DOI

10.1109/IEMBS.2003.1280860

Filename

1280860