Magnetic surfaces for the controlled manipulation of superparamagnetic microbeads

• Applicant: Professor Dr.-Ing. Jeffrey McCord
• Subject Area: Synthesis and Properties of Functional Materials ; Experimental Condensed Matter Physics
• Term: from 2014 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 258304063

The manipulation of superparamagnetic microbeads withfunctionalized surfaces as labels for single-molecule studies, for cellmanipulation, and detection of chemical or biological species in liquidenvironments are in the focus of the research project. Within theproject the fundamentals for the movement of superparamagneticbeads on functionalized magnetic surfaces will be explored. As abasis for the manipulation of beads, micro-lithographically patternedmagnetic surfaces in the form of array elements creating aninterconnecting magnetic network will be investigated. The transportof individual beads is performed by micro-magnetic objects such ascharged magnetic domain walls or switchable magnetizationstructures. Within the project the controlled movement of microbeadsalong magnetic structures with the help of variable multi-axismagnetic field protocols will be investigated. Different approaches arebeing explored for the transport of superparamagnetic particles inliquid suspensions. Moreover, hydrodynamic effects will be utilized byapplying temporal and angle varying magnetic fields with differentfrequency components. The lateral distribution of the magneticpatterns and the corresponding motion of the microbeads areanalyzed directly by complementary in-situ magnetic and bright-fieldoptical microscopy. The investigations will be supported by in depthsimulations. The research will open up new ways to laterallymanipulate marked biological objects, to facilitate a controlledmovement of particles in microfluidic environments over substantialdistances, and in that way provide the foundations for themanipulation and separation of biological objects in integratedflowless lab-on-chip devices.

• DFG Programme: Research Grants