Title
Improvement of Depth Profiling into Biotissues Using Micro Electrical Impedance Spectroscopy on a Needle with Selective Passivation.
Abstract
A micro electrical impedance spectroscopy (EIS)-on-a-needle for depth profiling (mu EoN-DP) with a selective passivation layer (SPL) on a hypodermic needle was recently fabricated to measure the electrical impedance of biotissues along with the penetration depths. The SPL of the mu EoN-DP enabled the sensing interdigitated electrodes (IDEs) to contribute predominantly to the measurement by reducing the relative influence of the connection lines on the sensor output. The discrimination capability of the mu EoN-DP was verified using phosphate-buffered saline (PBS) at various concentration levels. The resistance and capacitance extracted through curve fitting were similar to those theoretically estimated based on the mixing ratio of PBS and deionized water; the maximum discrepancies were 8.02% and 1.85%, respectively. Depth profiling was conducted using four-layered porcine tissue to verify the effectiveness of the discrimination capability of the mu EoN-DP. The magnitude and phase between dissimilar porcine tissues (fat and muscle) were clearly discriminated at the optimal frequency of 1 MHz. Two kinds of simulations, one with SPL and the other with complete passivation layer (CPL), were performed, and it was verified that the SPL was advantageous over CPL in the discrimination of biotissues in terms of sensor output.
Year
DOI
Venue
2016
10.3390/s16122207
SENSORS
Keywords
Field
DocType
electrical impedance spectroscopy,hypodermic needle,interdigitated electrodes,selective passivation,depth profiling,biotissues
Penetration (firestop),Analytical chemistry,Capacitance,Curve fitting,Hypodermic needle,Electronic engineering,Electrical impedance,Dielectric spectroscopy,Engineering,Passivation,Electrode
Journal
Volume
Issue
ISSN
16
12.0
1424-8220
Citations 
PageRank 
References 
0
0.34
4
Authors
3
Name
Order
Citations
PageRank
Joho Yun100.34
Hyeon Woo Kim200.34
Jong-Hyun Lee34410.32