High-Density Electrical Recording and Impedance Imaging With a Multi-Modal CMOS Multi-Electrode Array Chip.

Area of Science:

• Neuroscience
• Bioelectronics
• Materials Science

Background:

• Multi-electrode arrays (MEAs) are crucial for studying electrophysiological dynamics in cells and tissues.
• Active MEAs using CMOS technology offer superior single-cell resolution, reduced electrode size, and enhanced functionality compared to passive devices.
• Current MEA systems often lack multi-modality, limiting their application in studying complex biological phenomena.

Purpose of the Study:

• To design and characterize a novel CMOS MEA chip with high electrode density and multiple operational modalities.
• To utilize the MEA for monitoring the growth and electrophysiological activity of primary rat hippocampal neurons.
• To assess the impact of electrode size on neuronal signal recording and noise levels.

Main Methods:

• Development of a CMOS MEA chip featuring 16,384 titanium nitride electrodes organized into 16 active areas.
• Integration of 6 independent operational modalities, including impedance monitoring and voltage recording.
• Recording of neuronal electrophysiological activity and impedance measurements over time, confirmed by fluorescent staining.

Main Results:

• The MEA successfully monitored the growth and development of primary rat hippocampal neurons.
• Electrophysiological activity was assessed, showing a mean spike amplitude of 144.8 ± 84.6 μV.
• Impedance measurements at 1 kHz and 30 kHz sampling rate effectively evaluated cellular adhesion and growth.

Conclusions:

• The multi-modal CMOS MEA chip enables simultaneous assessment of diverse neuronal properties.
• The high-density electrode configuration and varied electrode sizes allow for detailed observation of cell culture evolution.
• This technology holds significant potential for fundamental neuroscience research and accelerating drug development.