Pulsed magnetic field improves the transport of iron oxide nanoparticles through cell barriers

ACS Nano. 2013 Mar 26;7(3):2161-71. doi: 10.1021/nn3057565. Epub 2013 Feb 13.

Abstract

Understanding how a magnetic field affects the interaction of magnetic nanoparticles (MNPs) with cells is fundamental to any potential downstream applications of MNPs as gene and drug delivery vehicles. Here, we present a quantitative analysis of how a pulsed magnetic field influences the manner in which MNPs interact with and penetrate across a cell monolayer. Relative to a constant magnetic field, the rate of MNP uptake and transport across cell monolayers was enhanced by a pulsed magnetic field. MNP transport across cells was significantly inhibited at low temperature under both constant and pulsed magnetic field conditions, consistent with an active mechanism (i.e., endocytosis) mediating MNP transport. Microscopic observations and biochemical analysis indicated that, in a constant magnetic field, transport of MNPs across the cells was inhibited due to the formation of large (>2 μm) magnetically induced MNP aggregates, which exceeded the size of endocytic vesicles. Thus, a pulsed magnetic field enhances the cellular uptake and transport of MNPs across cell barriers relative to a constant magnetic field by promoting accumulation while minimizing magnetically induced MNP aggregation at the cell surface.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biological Transport, Active
  • Cell Membrane / metabolism*
  • Dogs
  • Drug Delivery Systems
  • Madin Darby Canine Kidney Cells
  • Magnetic Fields
  • Magnetite Nanoparticles* / chemistry
  • Magnetite Nanoparticles* / ultrastructure
  • Nanotechnology
  • Temperature

Substances

  • Magnetite Nanoparticles