Microtrap electrode devices for single cell trapping and impedance measurement

Area of Science:

• Biomedical Engineering
• Electrical Engineering
• Cell Biology

Background:

• Accurate single-cell electrical characterization is crucial for understanding cellular function and disease.
• Existing methods for cell trapping and impedance measurement often suffer from position-dependent variations.
• Developing robust microfluidic devices for reliable cell analysis remains a key challenge.

Purpose of the Study:

• To design and fabricate advanced electrode microtraps for single-cell trapping and impedance measurement.
• To investigate the impact of electrode geometry on electric field uniformity and measurement accuracy.
• To demonstrate the utility of these microtraps for precise electrical characterization of individual cells.

Main Methods:

• Fabrication of parallel and elliptical gold electrode microtraps using electroplating.
• COVENTORWARE simulation to analyze electric field distribution and uniformity.
• Impedance spectroscopy measurements on single HeLa cells within the microtraps at different positions.

Main Results:

• The fabricated microtraps eliminated the need for precise alignment between insulating traps and electrodes.
• Simulations showed improved electric field uniformity, reducing cell position dependency.
• Impedance measurements revealed minimal changes in cell resistance and capacitance (0.7-0.85%) across different positions within the elliptical microtraps.

Conclusions:

• The developed electrode microtraps offer an improved and convenient platform for single-cell electrical characterization.
• The enhanced electric field uniformity significantly reduces measurement errors caused by cell positioning.
• These microtraps pave the way for more accurate and reliable analysis of individual cell electrical properties.