Particle sorting in a mini step-split-flow thin channel: influence of hydrodynamic shear on transversal migration

Area of Science:

• Microfluidics
• Biotechnology
• Analytical Chemistry

Background:

• Conventional SPLITT devices utilize splitters, limiting miniaturization and flow rates.
• Reducing channel dimensions in SPLITT technology is challenging with traditional fabrication methods.

Purpose of the Study:

• To develop a miniaturized SPLITT device for rapid separation of micrometer-sized species.
• To investigate the impact of reduced channel dimensions on hydrodynamic forces and separation efficiency.

Main Methods:

• Development of a mini step-SPLITT channel, replacing traditional splitters with inlet and outlet steps.
• Fabrication utilizing classic methods allowing for straightforward reduction of channel dimensions.
• Experimental validation using particulate and biological species in binary mixtures.

Main Results:

• The mini step-SPLITT device achieves high axial velocities at low flow rates.
• Enhanced inertial lift forces and hydrodynamic shear-induced diffusion were observed.
• Highly enriched fractions of smaller species were successfully obtained from binary mixtures.

Conclusions:

• The mini step-SPLITT device offers a pathway to faster and more efficient microparticle separations.
• Eliminating splitters and reducing channel dimensions significantly improves separation performance.
• This technology holds potential for applications in biotechnology and analytical chemistry requiring rapid fractionation.