Optical method for measurement of magnetophoretic mobility of individual magnetic microspheres in defined magnetic field

The magnetophoretic mobility of magnetic microspheres, nanospheres and particles depends not only on type and amount of encapsulated magnetic compound, but also on microsphere-internal distribution, solvent system, porosity and other factors. Using a microscopic setup with automated digital image processing, different magnetic microspheres were investigated for size, acceleration and velocity of each single microsphere in the suspension. The overall magnetophoretic mobility (responsiveness to an external magnetic field) was not directly proportional to the saturation magnetization of the magnetic microspheres.