Synthesis, characterization, and in vitro testing of superparamagnetic iron oxide nanoparticles targeted using folic acid-conjugated dendrimers

Kevin J. Landmark, Stassi DiMaggio, Jesse Ward, Christopher Kelly, Stefan Vogt, Seungpyo Hong, Alina Kotlyar, Andrzej Myc, Thommey P. Thomas, James E. Penner-Hahn, James R. Baker, Mark M. Banaszak Holl, Bradford G. Orr

Research output: Contribution to journalArticleResearchpeer-review

143 Citations (Scopus)


Organic-coated superparamagnetic iron oxide nanoparticles (OC-SPIONs) were synthesized and characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. OC-SPIONs were transferred from organic media into water using poly(amidoamine) dendrimers modified with 6-TAMRA fluorescent dye and folic acid molecules. The saturation magnetization of the resulting dendrimer-coated SPIONs (DC-SPIONs) was determined, using a superconducting quantum interference device, to be 60 emu/g Fe versus 90 emu/g Fe for bulk magnetite. Selective targeting of the DC-SPIONs to KB cancer cells in vitro was demonstrated and quantified using two distinct and complementary imaging modalities: UV-visible and X-ray fluorescence; confocal microscopy confirmed internalization. The results were consistent between the uptake distribution quantified by flow cytometry using 6-TAMRA UV-visible fluorescence intensity and the cellular iron content determined using X-ray fluorescence microscopy.

Original languageEnglish
Pages (from-to)773-783
Number of pages11
JournalACS Nano
Issue number4
Publication statusPublished - 1 Apr 2008
Externally publishedYes


  • Cancer
  • Dendrimers
  • Magnetic nanoparticles
  • Phase transfer
  • Superparamagnetism
  • Targeted MRI contrast agents
  • X-ray fluorescence microscopy

Cite this