High-definition electroporation: Precise and efficient transfection on a microelectrode array.

Area of Science:

• Biomedical Engineering
• Cell Biology
• Microfluidics

Background:

• Intracellular delivery is crucial for applications like mRNA transfection and gene editing.
• Bulk electroporation techniques often require extensive optimization and exhibit high cytotoxicity.
• Current methods are not suitable for large-scale screening of delivery conditions.

Purpose of the Study:

• To develop an expedited workflow for optimizing electroporation-based intracellular delivery using microelectrode array (MEA) chips.
• To achieve high transfection efficiency with low cytotoxicity in primary fibroblasts.
• To demonstrate the utility of CMOS MEA technology for various intracellular delivery applications.

Main Methods:

• Utilized a high-definition microelectrode array (MEA) chip for multiplexed electroporation experiments.
• Varied five electric pulse parameters across 32 conditions to determine optimal electroporation parameters.
• Employed multiple linear regression modeling and validation for rapid optimization.
• Evaluated cytotoxicity and intracellular delivery efficiency.

Main Results:

• Optimized on-chip electroporation achieved no cell death, demonstrating low cytotoxicity.
• Successfully delivered small molecules, Cas9-GFP/sgRNA complexes, and mRNA encoding mCherry.
• Achieved high-efficiency, single-cell transfection with 81% mCherry expression on actuated electrodes.

Conclusions:

• The developed workflow significantly reduces empirical optimization for electroporation.
• CMOS MEA technology offers a powerful platform for efficient and low-cytotoxicity intracellular delivery.
• This approach holds vast potential for advancing primary cell transfection and other biomedical applications.