Fabrication and characterization of magnetic-vortex microdiscs for applying force in mechanobiological systems*

Applying controlled, localized force in 3D mechano-biological systems has been a technical hurdle for probing cell mechanics. Bio-functionalized magnetic microdiscs have been used to apply force to cancer cells triggering apoptosis because of the advantage of a near zero stray field magnetic vortex configuration that prevents agglomeration when in solution.[1] In this work, we have fabricated discs with diameters ranging from 0.5 – 10 μm through lithography and sputtering. To guide the design of the microdiscs for biological applications, micromagnetic simulations, formulated with the Landau-Lifshitz equation, were performed using MUMAX3. Atomic force microscopy, small angle x-ray reflectivity, and scanning electron microscopy results confirm the desired characteristics of the discs.


[1]Kim, D.-H. et.al. Biofunctionalized magnetic-vortex microdiscs for targeted cancer cell destruction. Nat. Mater. 9(2): 165–171, 2010.