Magnetic counter-gravity flow separation of electrically prepolarised lymphoid cells

Area of Science:

• Biophysics
• Microfluidics
• Cell Separation Technology

Background:

• Traditional cell separation methods face challenges with efficiency and cell viability.
• Microfluidic devices offer precise control over cellular environments.
• Live cell separation is crucial for diagnostics and research.

Purpose of the Study:

• To propose and validate a novel principle for differential separation of live cells from a main flow using Lorentz forces.
• To investigate the influence of electric current direction on cell and microsphere sampling.
• To assess the effectiveness of the microfluidic device for cell enrichment and extraction.

Main Methods:

• Fabrication of a microfluidic device with insulated electrodes and internal conductor wires.
• Application of electric current to generate Lorentz forces on polarisable particles.
• Testing with polystyrene microspheres and lymphoid cell lines (DOHH2, K562).
• Analysis of induced vertical motion and cell concentration changes.

Main Results:

• Lorentz forces were successfully imposed, inducing consistent vertical motion in cells and microspheres.
• Electric current direction directly influenced the number of cells sampled.
• The device effectively increased cell extraction from a main flow.
• Enrichment of DOHH2 cells in a mixed population with K562 was achieved.
• Parameter limitations (potential-current) were found to be cell-type dependent.

Conclusions:

• A novel microfluidic approach utilizing Lorentz forces enables effective differential cell separation.
• The method shows promise for applications in cell purification and concentration.
• Further optimization based on cell-specific properties is warranted for broader applicability.