Title :
Microelectrical impedance tomography for biophysical characterization of thin film biomaterials
Author :
Linderholm, P. ; Schoch, R. ; Renaud, Ph.
Author_Institution :
MicroSyst. Lab., Ecole Polytech. Fed. de Lausanne, Switzerland
Abstract :
We present a new method for measuring the electrical resistivities of a stratified sample of thin biomaterials or tissue layers. The presented technique makes use of impedance measurements between 11 pairs of electrodes separated by varying distances. The electrodes are made of gold stripes, 20-500 /spl mu/m wide and 8 mm long. We used hydrogels of poly-hydroxyethyl methacrylate (pHEMA) as a model material for our measurements. By changing the concentration of cross-linker we were able to tune the resistivity of the hydrogel between 1,000 /spl Omega/m and 17,000 /spl Omega/m. Using these hydrogels we were able to detect a change in resistivity of a 120 /spl mu/m layer lying 250 /spl mu/m into the sample.
Keywords :
bioelectric phenomena; biological tissues; biomedical electrodes; biomedical materials; electric impedance imaging; electrical resistivity; microelectrodes; polymer gels; thin films; 1000 to 17000 ohmm; 20 to 500 micron; 8 mm; biophysical characterization; electrical resistivity; electrodes; hydrogels; impedance measurements; microelectrical impedance tomography; poly-hydroxyethyl methacrylate; thin film biomaterials; tissue layers; Conductivity; Electrical resistance measurement; Electrodes; Equations; Impedance measurement; Microelectrodes; Polymers; Skin; Tomography; Transistors;
Conference_Titel :
TRANSDUCERS, Solid-State Sensors, Actuators and Microsystems, 12th International Conference on, 2003
Conference_Location :
Boston, MA, USA
Print_ISBN :
0-7803-7731-1
DOI :
10.1109/SENSOR.2003.1215308
