Research Of Anti-magnetic Micro-manipulation Devices Based On Megneto-archimedes Effect

Most of the particles, such as cells, have weak diamagnetic propertiesin nature world. When these diamagnetic materials are exposed toparamagnetic ambient and magnetic field is applied, they will take4forcesincluding diamagnetic force, gravity, diamagnetic buoyancy, andArchimedean buoyancy. The beads can be stabilized suspension at a point inspace where the four forces achieve balance. Based on themagneto-Archimedes effect, This article utilizes the diamagnetic propertiesof most natural materials, combined with MEMS technology, to achieve thecapture and manipulation of the biological particles in chips with the unique"anti-magnetic tweezers trap".An efficient and convenient way to levitate and manipulate micro beadsis reported, in which coils and soft magnetic materials are used to generate amagnetic field. The levitation is based on diamagnetic buoyancy, and themain structure of this device is made into spiral switch arrays so as to simplify the interconnection and magnetic field control. The design,modeling, fabrication of the device for diamagnetic beads manipulation andthe control system is given in detail.Experiments show that the anti-magnetic micro-manipulationtechniques based on MEMS can achieve the micro-manipulation of thebiological particles, such as collection, separation, and has its own uniqueadvantages, is expected to become a new type of micro-manipulationtechniques.