PMC

Schematic of process of cell chain formation in ferrofluid. (a) Suspension of cells in ferrofluid assumes a random orientation in the absence of a magnetic field. (b) The suspended cells form linear arrangements in ferrofluid in presence of magnetic field (arrows), where the ferrofluid particles shepherd the cells into chains due to their induced magnetic dipoles. (c) Linear arrangement of cells adherent to cell-adhesive surface survive and grow upon removal of ferrofluid and magnetic field. (d) Schematic of BSA-passivated nanoparticle synthesis.

(a) Schematic representation of preparation of magnetic phthalocyanines: Step 1) ferrofluid produced with the mixture of Fe₃O₄ and oleic acid; Step 2) reaction of ferrofluid with phthalocyanines. (b) Influence of the magnetic field under the suspension of Fe₃O₄@OA/Pc in ethanol.

Flow rate effect on diamagnetic yeast cell fractionation by morphology in 0.1× EMG 408 ferrofluid. The flow rate ratio between the sheath ferrofluid and the yeast cell suspension is fixed at 20 when the latter is varied from 5 μl/h to 13 μl/h. The left and right plots at each flow rate show the experimental cell image and the numerically predicted cell trajectories, respectively.

(a) Néel and Brown relaxation times calculated over a range of particle sizes for a water-based magnetite ferrofluid []; (b) Imaginary part of susceptibility of maghemite based aqueous suspension in comparison to the identical particles immobilized in the gel. Reprinted with permission [,]. Copyright 2021, Elsevier.