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We present initial results on the fabrication and testing of micropatternable conductive nanocomposite polymer (C-NCP)
electrodes for tissue impedance measurements. We present these proof-of-concept results as a first step toward the
realization of our goal: an improved Electrical Impedance Scanning (EIS) system, whereby tissue can be scanned for
cancerous tissue and other anomalies using large arrays of highly flexible microfabricated electrodes. Previous
limitations of existing EIS system are addressed by applying polymer based microelectromechanical system (MEMS)
technology. In particular, we attempt to minimize mechanical skin contact issues through the use of highly compliant
elastomeric polymers, and increase the spatial resolution of measurements through the development of microelectrodes
that can be micropatterned into large, highly dense arrays. We accomplish these improvements through the development
of C-NCP electrodes that employ silver nanoparticle fillers in an elastomer polymer base that can be easily patterned
using conventional soft lithography techniques. These new electrodes are tested on conventional tissue phantoms that
mimic the electrical characteristics of human tissue. We characterize the conductivity of the electrodes (average
resistivity of 7x10-5 ohm-m +/- 14.3% at 60 wt-% of silver nanoparticles), and further employ the electrodes for
impedance characterization via Cole-Cole plots to show that measurements employing C-NCP electrodes are comparable
to those obtained with normal macroscopic metal electrodes. We also demonstrate anomaly detection using our highly
flexible Ag/AgCl C-NCP electrodes on a tissue phantom.
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