Particle flow control by induced dipolar interaction of superparamagnetic microbeads
Magnetic particles diluted in liquid agglomerate in rod-like particle arrays if an external homogeneous magnetic field is applied. This work introduces a method to specifically exploit particle–particle interaction to obtain flow control of magnetic particles without changing the motion state of the carrier liquid. Experiments show the possibility to uncouple the particle flux from the motion state of liquid. We show how this method may be applied to design a microfluidic geometry in which the particle flow in a specific direction is either enabled or suppressed by the relative orientation of the fluid velocity and the external field.
KeywordsSuperparamagnetic beads Dipole–dipole interaction Particle chains Particle suprastructures
The authors would like to thank the SFB 613 and the FOR 945 for financial support in the framework of the project K3 and the project 3, respectively.
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