Development of a microfluidic device for cell concentration and blood cell-plasma separation

Area of Science:

• Biomedical Engineering
• Microfluidics
• Lab-on-a-Chip Technology

Background:

• Effective cell concentration and plasma separation are crucial for various diagnostic applications.
• Existing microfluidic methods face challenges in achieving high efficiency and cell viability.

Purpose of the Study:

• To design, fabricate, and test a novel microfluidic device for efficient cell concentration and blood-plasma separation.
• To leverage the Fahraeus-Lindqvist and Zweifach-Fung effects for enhanced microfluidic performance.
• To validate the device's utility as a sample preparation module for lab-on-a-chip diagnostic platforms.

Main Methods:

• Device design incorporating a main channel with symmetrically branched channels and pre-junction constrictions.
• Theoretical and numerical analysis for microchannel network optimization and flow rate prediction.
• Experimental validation using microbeads, droplets, HL60 cells, and diluted blood samples.
• Performance quantification via Haemocytometer and Fluorescence-Activated Cell Sorter (FACS), with cell viability assessment using Trypan Blue.

Main Results:

• Achieved a seven-fold concentration of HL60 cells.
• Demonstrated 70% purification efficiency and 80% plasma recovery for diluted blood samples (1:20).
• Confirmed high cell viability (>99%) post-processing, indicating minimal cell lysis.

Conclusions:

• The developed microfluidic device effectively concentrates cells and separates plasma from blood.
• The integrated constrictions enhance cell focusing and separation performance.
• The device shows significant potential as a sample preparation module for point-of-care diagnostics.