Single channel layer, single sheath-flow inlet microfluidic flow cytometer with three-dimensional hydrodynamic...

Area of Science:

• Biotechnology
• Microfluidics
• Analytical Chemistry

Background:

• Flow cytometry relies on three-dimensional (3D) hydrodynamic focusing for accurate particle analysis.
• Existing microfluidic flow cytometers often involve complex fabrication and operation due to multi-layered designs and intricate fluidic interconnections.
• A need exists for simplified, robust microfluidic devices for practical flow cytometry applications.

Purpose of the Study:

• To develop a simplified microfluidic flow cytometer utilizing a single channel layer and a single sheath-flow inlet for 3D hydrodynamic focusing.
• To demonstrate the feasibility and performance of this novel device for flow cytometry and biological applications.

Main Methods:

• Computational fluid dynamics (CFD) simulations were employed to model and optimize the flow fields.
• A microfluidic device with perpendicular sheath-flow introduction was designed and fabricated.
• Experimental characterization involved confocal microscopy to visualize flow fields and flow cytometry for bead and cell analysis.

Main Results:

• CFD simulations confirmed successful 3D hydrodynamic focusing under optimized flow conditions.
• Confocal microscopy validated the simulated flow fields, showing clear cross-sectional views of the 3D focusing.
• Flow cytometry experiments demonstrated high detection performance for fluorescence beads and cells, comparable to conventional systems.

Conclusions:

• The developed single-layer, single-inlet microfluidic device effectively achieves 3D hydrodynamic focusing for flow cytometry.
• This simplified design offers a practical and robust platform for routine biological analyses in laboratory settings.
• The 3D hydrodynamic focusing channel design has potential applications in advancing lab-on-a-chip research.