Resistivity probing of multi-layered tissue phantoms using microelectrodes

Area of Science:

• Electrical Engineering
• Biomedical Engineering
• Materials Science

Background:

• Accurate characterization of layered materials is crucial for various applications.
• Developing non-invasive methods for probing tissue properties is a significant challenge.

Purpose of the Study:

• To present a novel microelectrode array system for discriminating between different electrical resistivities in thin, layered samples.
• To develop and validate a hydrogel-based tissue phantom for testing the microelectrode system.
• To explore potential clinical applications of this resistivity measurement technique.

Main Methods:

• Fabrication of a rectangular microelectrode array with varying widths (20-500 microm).
• Development of a hydrogel tissue phantom using 2-hydroxyethyl methacrylate (HEMA) with tunable resistivity (100 omegam to 100 komegam).
• Characterization of the tissue phantoms using bipolar measurements across a frequency range of 100 Hz to 30 MHz.

Main Results:

• The microelectrode array successfully discriminated between different resistivities in layered samples.
• Calculated relative resistivity distribution of a three-layered structure agreed within 7% of bulk measurements.
• Hydrogel resistivity was effectively tuned by altering composition and ionic strength.

Conclusions:

• The developed microelectrode array system is effective for characterizing layered materials with varying electrical properties.
• The hydrogel tissue phantom serves as a reliable model for testing resistivity measurement techniques.
• This technology holds promise for clinical applications such as probing epithelial tissue and skin cancer screening.