Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MA: Fachverband Magnetismus
MA 36: Magnetic Particles / Clusters
MA 36.4: Vortrag
Donnerstag, 30. März 2023, 10:15–10:30, HSZ 401
Reversible on-chip focusing and clustering of superparamagnetic beads using engineered magnetic domain patterns — •Rico Huhnstock1, Lukas Paetzold1, Maximilian Merkel1, Piotr Kuświk2, and Arno Ehresmann1 — 1Institute of Physics and Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel, Heinrich-Plett-Str. 40, D-34132 Kassel — 2Institute of Molecular Physics, Polish Academy of Sciences, M. Smoluchowskiego 17, Poznań 60-179, Poland
To realize fast and reliable point-of-care medical diagnostics, incorporating magnetic particles into a Lab-on-a-chip technology platform is considered promising. For sensitive detection, binding of the analyte species to surface-functionalized particles and subsequent formation of particle aggregates with the analyte acting as molecular bridges is a possible route [1]. As close proximity between particles is required for this scheme, we demonstrate in this work a locally defined focusing of superparamagnetic microparticles within an aqueous medium above a magnetically patterned flat substrate. Combining the magnetic stray field landscape that originates from periodic magnetic stripe domains of gradually decreasing/increasing length with external magnetic field pulses, converging and diverging motion trajectories were induced for the particles. Ultimately, this led to a controlled formation and decomposition of closely packed particle clusters. We will discuss how the observed behavior is determined by the acting forces and how it is influenced by the duration of the external field pulses.
[1] Rampini et al. (2021), Scientific Reports, 11(1):5302.