Superparamagnetic iron oxide nanoparticle probes for molecular imaging

Ann Biomed Eng. 2006 Jan;34(1):23-38. doi: 10.1007/s10439-005-9002-7. Epub 2006 Feb 16.


The field of molecular imaging has recently seen rapid advances in the development of novel contrast agents and the implementation of insightful approaches to monitor biological processes non-invasively. In particular, superparamagnetic iron oxide nanoparticles (SPIO) have demonstrated their utility as an important tool for enhancing magnetic resonance contrast, allowing researchers to monitor not only anatomical changes, but physiological and molecular changes as well. Applications have ranged from detecting inflammatory diseases via the accumulation of non-targeted SPIO in infiltrating macrophages to the specific identification of cell surface markers expressed on tumors. In this article, we attempt to illustrate the broad utility of SPIO in molecular imaging, including some of the recent developments, such as the transformation of SPIO into an activatable probe termed the magnetic relaxation switch.

Publication types

  • Review

MeSH terms

  • Animals
  • Contrast Media / chemistry
  • Contrast Media / pharmacology*
  • Dextrans
  • Drug Delivery Systems / methods
  • Ferrosoferric Oxide
  • Humans
  • Image Enhancement / methods
  • Iron / chemistry
  • Iron / pharmacology*
  • Magnetic Resonance Imaging* / methods
  • Magnetics
  • Magnetite Nanoparticles
  • Molecular Probe Techniques
  • Molecular Probes / chemistry
  • Molecular Probes / pharmacology*
  • Nanostructures / chemistry*
  • Nanotechnology* / methods
  • Oxides / chemistry
  • Oxides / pharmacology*


  • Contrast Media
  • Dextrans
  • Magnetite Nanoparticles
  • Molecular Probes
  • Oxides
  • Iron
  • ferumoxides
  • Ferrosoferric Oxide