Continuous On-Chip Cell Separation Based on Conductivity-Induced Dielectrophoresis with 3D Self-Assembled Ionic...

Area of Science:

• Biomedical Engineering
• Microfluidics
• Cell Separation Technology

Background:

• Dielectrophoresis (DEP) is crucial for cell separation but often limited by expensive noble metal electrodes, high voltage requirements, and discontinuous processes.
• Existing DEP devices face challenges including high fabrication costs and operational complexity.

Purpose of the Study:

• To develop a cost-effective and continuously operating DEP device for cell separation.
• To utilize liquid electrodes and conductivity gradients for enhanced on-chip cell separation.

Main Methods:

• Fabrication of a polydimethylsiloxane (PDMS) microfluidic device with ionic liquid-based liquid electrodes.
• Application of positive dielectrophoresis (DEP) leveraging a conductivity gradient for cell manipulation.
• Separation of polystyrene microbeads, PC-3 human prostate cancer cells (live/dead), and MDA-MB-231 breast cancer cells from human adipose-derived stem cells (ADSCs).

Main Results:

• Achieved continuous separation of polystyrene microbeads (94.7% deflection) and PC-3 cells (1.2% deflection).
• Successfully differentiated live (89.8% deflection) and dead (13.2% deflection) PC-3 cancer cells.
• Separated MDA-MB-231 breast cancer cells from ADSCs with high purity (81.8% ADSCs, 82.5% MDA-MB-231).

Conclusions:

• The developed microfluidic device offers an affordable and easy-to-operate solution for continuous cell separation using conductivity-induced DEP.
• This technology shows significant potential for various cell separation applications, including cancer cell and stem cell isolation.
• Liquid electrodes provide a viable and cost-effective alternative to traditional noble metal electrodes in DEP devices.