Arrays of NdFeB Clusters in PDMS Background Used to Levitate T47D Human Cells

Abstract

Sorting and trapping cells play an important role in fundamental cellular and biology research that enables the study of single-cell behaviors, which are different in comparison with a cluster of cells. Contactless handling techniques using different optical, mechanical, or magnetic phenomena have been studied for single-cell trapping. Among them, the diamagnetic force created by magnetic structures on cells is significant and stable both in time and in space. In this work, arrays of hard magnetic clusters in the PDMS background (hereafter called magnetic structure) were successfully fabricated using the magnetic imprinting method. The magnetic structure shows a proper magnetic property and the possibility to sort and trap T47D single cells via the diamagnetic levitation phenomenon at defined positions, which are both experimentally observed and theoretically calculated. The obtained results show the promise of developing a simple way to separate directly living cells.

Fig. 4 T47D cells levitate on the magnetic structure covered by a Si piece (a), dependence of the theoretical total force in the z-axis affecting a cell which is at the center of the gap between 4 squared-shape NdFeB clusters on the height from the surface of the magnetic structure (b).