Paramagnetic lipid-coated silica nanoparticles with a fluorescent quantum dot core: a new contrast agent platform for multimodality imaging

Bioconjug Chem. 2008 Dec;19(12):2471-9. doi: 10.1021/bc800368x.


Silica particles as a nanoparticulate carrier material for contrast agents have received considerable attention the past few years, since the material holds great promise for biomedical applications. A key feature for successful application of this material in vivo is biocompatibility, which may be significantly improved by appropriate surface modification. In this study, we report a novel strategy to coat silica particles with a dense monolayer of paramagnetic and PEGylated lipids. The silica nanoparticles carry a quantum dot in their center and are made target-specific by the conjugation of multiple alphavbeta3-integrin-specific RGD-peptides. We demonstrate their specific uptake by endothelial cells in vitro using fluorescence microscopy, quantitative fluorescence imaging, and magnetic resonance imaging. The lipid-coated silica particles introduced here represent a new platform for nanoparticulate multimodality contrast agents.

Publication types

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

MeSH terms

  • Animals
  • Cattle
  • Cell Line
  • Contrast Media / chemistry*
  • Fluorescence*
  • Gadolinium DTPA / chemistry
  • Humans
  • Hydrophobic and Hydrophilic Interactions
  • Lipids / chemistry*
  • Magnetic Resonance Imaging
  • Magnetics*
  • Polyethylene Glycols / chemistry
  • Quantum Dots*
  • Silicon Dioxide / chemistry*
  • Surface Properties


  • Contrast Media
  • Lipids
  • gadolinium stearylamide DTPA
  • Polyethylene Glycols
  • Silicon Dioxide
  • Gadolinium DTPA