Magnetic materials have been used in bioseparation for decades, typically in the form of nanometer to micrometer sized magnetic particles coated with biomolecular capture moieties, which are used to fish out biomaterials (e.g., proteins, viruses, and cells) and separate them from fluid mixtures with strong magnets. Magnetic beads are heavily used in cell separation and in genomics workflows.
Our research aims to improve the control of these magnetic objects at micron scales by creating precise magnetic field patterns on surfaces that are adjustable with an applied external field. Much of our research over the past decade has been focused on analyzing the non-linear dynamical transport properties of magnetic colloids when exposed to rotating or oscillatory fields, however, more recently we have been interesed in the applications of these tools for sorting cells in microfluidic chips for use in single cell analysis. Some of our key papers on this topic are provided below:
Physics of magnetic manipulation:
BB Yellen, O Hovorka, and G Friedman. "Arranging matter by magnetic nanoparticle assemblers." Proceedings of the National Academy of Sciences of the United States of America 102, no. 25 (2005): 8860-8864.
BB Yellen, RM Erb, HS Son, RH Jr, H Shang, and GU Lee. "Traveling wave magnetophoresis for high resolution chip based separations." Lab on a Chip 7, no. 12 (2007): 1681-1688.
L Gao, NJ Gottron, LN Virgin, and BB Yellen. "The synchronization of superparamagnetic beads driven by a micro-magnetic ratchet." Lab on a Chip 10, no. 16 (2010): 2108-2114.
L Gao, MA Tahir, LN Virgin, and BB Yellen. "Multiplexing superparamagnetic beads driven by multi-frequency ratchets." Lab on a Chip 11, no. 24 (2011): 4214-4220.
Applications of magnetic manipulation:
B Lim, V Reddy, X Hu, K Kim, M Jadhav, R Abedini-Nassab, Y-W Noh, YT Lim, BB Yellen, and C Kim."Magnetophoretic circuits for digital control of single particles and cells." Nature Communications 5 (2014).
R Abedini-Nassab, DY Joh, M Van Heest, C Baker, A Chilkoti, DM Murdoch, and BB Yellen."Magnetophoretic Conductors and Diodes in a 3D Magnetic Field." Advanced Functional Materials 26, no. 22 (2016): 4026-4034.
R Abedini-Nassab, DY Joh, F Albarghouthi, A Chilkoti, DM Murdoch, and BB Yellen. "Magnetophoretic transistors in a tri-axial magnetic field." Lab on a Chip 16, no. 21 (2016): 4181-4188.