title: The effects of magnetite (Fe₃O₄) nanoparticles on electroporation-induced inward currents in pituitary tumor (GH₃) cells and in RAW 264.7 macrophages.
abstract: OBJECTIVE
  Fe₃O₄ nanoparticles (NPs) have been known to provide a distinct image contrast effect for magnetic resonance imaging owing to their super paramagnetic properties on local magnetic fields. However, the possible effects of these NPs on membrane ion currents that concurrently induce local magnetic field perturbation remain unclear.
  
  
  METHODS
  We evaluated whether amine surface-modified Fe₃O₄ NPs have any effect on ion currents in pituitary tumor (GH₃) cells via voltage clamp methods.
  
  
  RESULTS
  The addition of Fe₃O₄ NPs decreases the amplitude of membrane electroporation-induced currents (I(MEP)) with a half-maximal inhibitory concentration at 45 μg/mL. Fe₃O₄ NPs at a concentration of 3 mg/mL produced a biphasic response in the amplitude of I(MEP), ie, an initial decrease followed by a sustained increase. A similar effect was also noted in RAW 264.7 macrophages.
  
  
  CONCLUSIONS
  The modulation of magnetic electroporation-induced currents by Fe₃O₄ NPs constitutes an important approach for cell tracking under various imaging modalities or facilitated drug delivery.
authors.affiliation: Department of Anesthesiology, National Cheng Kung University Hospital, College of Medicine, Tainan, Taiwan.
authors.forename: Yen-Chin
authors.initials: YC
authors.lastname: Liu
authors.forename: Ping-Ching
authors.initials: PC
authors.lastname: Wu
authors.forename: Dar-Bin
authors.initials: DB
authors.lastname: Shieh
authors.forename: Sheng-Nan
authors.initials: SN
authors.lastname: Wu
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D018274:Electroporation / Q000379:methods*; D017136:Ion Transport / Q000187:drug effects; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D010316:Particle Size; D018408:Patch-Clamp Techniques; D010911:Pituitary Neoplasms / Q000378:metabolism* / Q000473:pathology; D051381:Rats; D013481:Superoxides / Q000378:metabolism
chemical_list: D058185:Magnetite Nanoparticles; D013481:Superoxides