Electromagnetic micromotor for microfluidics applications

An electromagnetic micromotor has been developed that combines microcoils a nd magnetic microtips as stator elements and individual permanent magnet si ngle domain particles as rotors. The three-phase stator microcoils (with po les separated by 100 mum) are positioned outside the fluid, and the rotor ( a 40 mum long, 1 mum diam permanent magnet) spins in aqueous solution 50 mu m from the stator. The small size and essentially disposable rotors make th e magnetic micromotor attractive for use in microfluidics systems for vario us physical, chemical, and biological applications. (C) 2001 American Insti tute of Physics.