Send to

Choose Destination
J Phys Chem B. 2006 Sep 28;110(38):18958-64.

Sudden breakdown in linear response of a rotationally driven magnetic microparticle and application to physical and chemical microsensing.

Author information

Applied Physics Program, 2477 Randall Laboratory, The University of Michigan, Ann Arbor, Michigan 48109-1120, USA.


In this work, sensing magnetic microparticles were used to probe both the local pH and the viscosity-dependent nonlinear rotational behavior of the particles. The latter resulted from a critical transition marking a driven particle's crossover from phase-locking to phase-slipping with an externally rotating magnetic field, i.e., a sudden breakdown in its linear response that can be used to measure a variety of physical quantities. The transition from simple rotation to wobbling is described both theoretically and experimentally. The ability to measure both chemical and physical properties of a system could enable simultaneous monitoring of chemical and physical interactions in biological or other complex fluid microsystems.


Supplemental Content

Full text links

Icon for American Chemical Society
Loading ...
Support Center