Vortex-Enhanced Microfluidic Chip for Efficient Mixing and Particle Capturing Combining Acoustics with Inertia

Area of Science:

• Microfluidics
• Acoustic manipulation
• Inertial focusing
• Lab-on-chip technology

Background:

• Vortex-based microfluidics offers high efficiency, flexible control, and label-free manipulation.
• Existing vortex microfluidic devices have limitations in flow range and excitation voltage requirements.

Purpose of the Study:

• To develop an improved vortex-based acousto-inertial microfluidic chip.
• To achieve enhanced fluid and particle manipulation over a wider flow range and lower excitation voltage.
• To demonstrate the chip's capabilities in sample homogenization, particle manipulation, and red blood cell lysis.

Main Methods:

• Design of a chip integrating contraction-expansion arrays, vibrating microstructures, bubbles, and sharp edges.
• Characterization of flow patterns using fluorescence particle tracer experiments.
• Investigation of particle dynamics with high-speed imaging.
• Demonstration of red blood cell lysis utilizing microvortex-induced shear forces.

Main Results:

• The chip exhibits vigorous vortical fluid motions due to synergistic acoustic and inertial effects.
• Identified single- and double-vortex modes across various flow rates and excitation voltages.
• Achieved rapid and efficient sample homogenization at flow rates up to 200 μL/min with 15 Vpp excitation.
• Demonstrated continuous, reagent-free lysis of red blood cells.

Conclusions:

• The acousto-inertial microfluidic chip significantly improves upon existing vortex-based microfluidic technologies.
• The device offers high controllability and multifunctionality for various microfluidic applications.
• This technology holds potential for developing advanced miniaturized 'lab-on-chip' analytical systems in biological, chemical, and clinical fields.