A magnetic transfer method for sorting, collecting, transferring or dosing microparticles (22) or magnetic particles either in the same liquid (23) or from one liquid (23a) into another (23b) by using a magnetic field. The transfer device (10) comprises a magnet (13) placed inside a protective coating (21), and the collection or dozing is accomplished by changing the magnetic field of the magnet (13). The changing of the magnetic field is effected by using a ferromagnetic body, such as a plate or tube (12), comprised in the transfer device, in such manner that, when micro-particles are to be collected, the magnet is partially or completely outside the ferromagnetic body and, when the particles are to be released or dozed, the magnet is partially or completely inside or behind the ferromagnetic body.
