A Novel Tissue Culture Tray for the Study of Magnetically Induced Rotation and Translation of Iron Oxide Nanoparticles

Iron oxide nanoparticles (IONs) hold promise for enhancing drug delivery for cancer, stroke, and other diseases. Here, we demonstrate the use of a multiple-lane tissue culture tray and rotating permanent magnet to study magnetically induced rotation and translation (MIRT) of magnetic microbeads (MBs). MBs are nanoparticle aggregates with single-crystalline magnetite cores which can be moved by surface traction. The MIRT tray was produced by additive manufacturing (3-D printing) or subtractive manufacturing (milling) of acrylic. The velocity of MBs in the MIRT tray through phosphate-buffered saline, culture media with fetal bovine serum (FBS), and 100 FBS was measured from 7.5 to 30cm above the rotating magnet. A maximum velocity of greater than 5cms occurred at a distance of 22.5cm. Cultured rabbit aortic endothelial cells, grown in lanes of the sterilized MIRT tray, cause some reduction in MB velocity. We conclude that MBs are easily rotated and moved at physiologic distances by the rotating permanent magnet. Thus, MIRT can potentially be used to direct MBs in clinical drug delivery, and the MIRT tray provides a convenient model system for testing variables which can affect ION movement.