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Updated: Feb 13, 2026

Pneumatically Driven Microfluidic Platform for Micro-Particle Concentration
Published on: February 1, 2022
Quantification of colloidal filtration of polystyrene micro-particles on glass substrate using a microfluidic device
Jianfeng Sun1, Nil Tandogan2, April Z Gu3
1Department of Mechanical & Industry Engineering, Northeastern University, Boston, MA 02115, USA.
Abstract:
A microfluidic device was designed to investigate filtration of particles in an electrolyte in the presence of liquid flow. Polystyrene spheres in potassium chloride solution at concentrations of 3-100 mM were allowed to settle and adhere to a glass substrate. A particle free solution at the same concentration was then flushed through the microfluidic channel at 0.03-4.0 mL/h. As the hydrodynamic drag on the adhered particles exceeded the intersurface interaction with the substrate, "pull-off" occurred and the particles detached. Filtration efficiency, α, was shown to a function of both ionic concentration of the liquid medium and flow speed, consistent with a phenomenological model based on the classical DLVO theory. The results elucidates the underlying physics of filtration.
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