Print Email Facebook Twitter Biological Magnetometry: Torque on Superparamagnetic Beads in Magnetic Fields Title Biological Magnetometry: Torque on Superparamagnetic Beads in Magnetic Fields Author Van Oene, M.M. Dickinson, L.E. Pedaci, F. Köber, M. Dulin, D. Lipfert, J. Dekker, N.H. Faculty Applied Sciences Department BN/Bionanoscience Date 2015-05-27 Abstract Superparamagnetic beads are widely used in biochemistry and single-molecule biophysics, but the nature of the anisotropy that enables the application of torques remains controversial. To quantitatively investigate the torques experienced by superparamagnetic particles, we use a biological motor to rotate beads in a magnetic field and demonstrate that the underlying potential is ? periodic. In addition, we tether a bead to a single DNA molecule and show that the angular trap stiffness increases nonlinearly with magnetic field strength. Our results indicate that the superparamagnetic beads’ anisotropy derives from a nonuniform intrabead distribution of superparamagnetic nanoparticles. To reference this document use: http://resolver.tudelft.nl/uuid:7c5f7686-c8b0-4b18-b2b4-c9f1247eb5e4 Publisher American Physical Society ISSN 0031-9007 Source https://doi.org/10.1103/PhysRevLett.114.218301 Source Physical Review Letters, 114, 2015 Part of collection Institutional Repository Document type journal article Rights © 2015 American Physical Society Files PDF vanOene_2015.pdf 1.45 MB Close viewer /islandora/object/uuid:7c5f7686-c8b0-4b18-b2b4-c9f1247eb5e4/datastream/OBJ/view