Size-Dependent Particle Filteration using Magnetically Driven Microtool and Centrifugal Force in Microchip

We succeeded in size-dependent filtration of microparticles by rotation of magnetically driven microtool (MMT) and centrifugal force in a microchip. Novelties of this paper are summarized as follows. (1) Filtering efficiency was improved than filtration by solely centrifugal force by MMT rotation. (2) Clogging of microparticles was avoided by swirling flow generated by rotation of 3D-MMT with fins. (3) This filtration is robust against pressure fluctuation in a microchip by mechanical particle separation using internal walls. Microparticles with different sizes flow in spiral microchannels and are separated according to their sizes by pass through under each sidewall of microchannels by centrifugal force. MMT is set inside the microchamber and rotated by external magnetic force. Rotation of MMT avoids the clogging of the microparticles and enhances the sorting efficiency. We demonstrated filtration of the microparticles in a microchip using 3D-MMT rotation and centrifugal force.