A contactless dielectrophoretic handling of diamagnetic levitating water droplets in air
Résumé
In previous works, microfabricated permanent magnets were designed and fabricated for levitating picoliter water droplets in air. Manipulating levitating water droplets is a contamination-free alternative to digital-microfluidic systems on surface used in biotechnologies. Here, the possibility of adding dielectrophoretic (DEP) forces to control the position of levitating droplets along a magnetic groove is numerically evaluated. The diamagnetic forces are computed using CADES framework while the DEP forces are computed with Comsol Multiphysicsä (Finite Element Method). Errors made using the point dipole model and the 2D approximation are evaluated by comparison with the full 3D problem. Based on these results, an electric sequence for polarizing planar interdigitated ITO electrodes is proposed in order to provide a stable and accurate control of the droplets micropositioning along the gap.