A Vacuum-Integrated Centrifugal Microfluidic Chip for Density-Based Separation of Microparticles

Abstract

Here we present a new vacuum-integrated centrifugal microfluidic chip for the density-based separation of microparticles. A sample was loaded in a fluidic channel using the gas permeability feature of polydimethylsiloxane (PDMS) membrane between fluidic and control channels. Vacuum was applied from control channel to drive a density media and then the sample containing microparticles in the dead-end fluidic channel. Afterwards, the chip was disconnected from the vacuum and it was centrifugated. If the sample contains microparticles denser than the density media, the microparticles are sedimented at the end of the microfluidic channel so that these particles can be separated from remaining the lower density particles. With this approach, we separated 1.09 g/mL microparticles with 82,6% efficiency and 99% purity from 1.02 g/mL microparticles. Separated particles in the microfluidic chip can also be inspected under a microscope for further analysis. This simple approach offers high efficient density-based separation of microparticles with close densities.

Core–Shell Particles: From Fabrication Methods to Diverse Manipulation Techniques

“…A typical magnetic levitation platform consists of two magnets with the same poles facing each other, forming a non-uniform magnetic field between them. Particles of different densities levitate at distinct heights depending on the balance between buoyancy force and magnetic force [ 164 ]. This method was reported to sort particles with a density difference of 60 kg/m 3 [ 165 ].…”

Core -Shell Particles: from Fabrication Methods to Diverse Manipulation Techniques

“…Light and heavy particles levitate at different heights depending on the balance between buoyancy and magnetic force. [170] This method was reported to sort particles with a density difference of 60kg/m 3 . [171]…”