Improving the capturing ability of swirl-based microfluidic chip by introducing baffle wall

Area of Science:

• Microfluidics
• Biotechnology
• Fluid dynamics

Background:

• Microfluidics offers nondestructive control for microparticle manipulation.
• Swirling stagnation points are a key microfluidic biotechnology for particle handling.
• Existing methods have limitations in controlling the stagnation point's range.

Purpose of the Study:

• To improve microparticle regulation and control within microfluidic systems.
• To investigate the effect of baffle walls on microchannel flow fields.
• To achieve a wider adjustment range for the swirling stagnation point.

Main Methods:

• Introduced baffle walls into a two-microchannel flow field.
• Applied wall attachment jet theory to analyze baffle wall effects.
• Utilized finite volume method simulation to model the swirling flow region (SFR).
• Calculated swirling strength to assess particle-capturing ability.
• Validated simulation with experiments on a printed microfluidic chip.

Main Results:

• Baffle walls significantly influence the swirling flow region (SFR).
• A convex baffle wall configuration achieved global adjustment of the stagnation point.
• This represents a significant improvement over previous methods with limited range adjustment.
• The study demonstrated the reliability of the simulation and experimental methods.

Conclusions:

• Baffle walls are effective in enhancing microfluidic flow field structures.
• Convex baffle walls enable superior regulation of stagnation points and microparticle manipulation.
• This technology holds promise for applications in single-cell analysis and studying bio/chemical substance effects.