Biocompatible magnetofluorescent probes: luminescent silicon quantum dots coupled with superparamagnetic iron(III) oxide

ACS Nano. 2010 Sep 28;4(9):5131-8. doi: 10.1021/nn101016f.

Abstract

Luminescent silicon quantum dots (SiQDs) are gaining momentum in bioimaging applications, based on their unique combination of optical properties and biocompatibility. Here, we report the development of a multimodal probe that combines the optical properties of silicon quantum dots with the superparamagnetic properties of iron oxide nanoparticles to create biocompatible magnetofluorescent nanoprobes. Multiple nanoparticles of each type are coencapsulated within the hydrophobic core of biocompatible phospholipid-polyethyleneglycol (DSPE-PEG) micelles. The size distribution and composition of the magnetofluorescent nanoprobes were characterized by transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS). Enhanced cellular uptake of these probes in the presence of a magnetic field was demonstrated in vitro. Their luminescence stability in a prostate cancer tumor model microenvironment was demonstrated in vivo. This paves the way for multimodal silicon quantum-dot-based nanoplatforms for a variety of imaging and delivery applications.

Publication types

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

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Coated Materials, Biocompatible / chemistry*
  • Coated Materials, Biocompatible / toxicity
  • Female
  • Ferric Compounds / chemistry*
  • Fluorescent Dyes / chemistry*
  • Fluorescent Dyes / toxicity
  • Humans
  • Macrophages / cytology
  • Magnetics*
  • Male
  • Mice
  • Molecular Imaging / methods*
  • Optical Phenomena
  • Prostatic Neoplasms / pathology
  • Quantum Dots*
  • Silicon / chemistry*

Substances

  • Coated Materials, Biocompatible
  • Ferric Compounds
  • Fluorescent Dyes
  • ferric oxide
  • Silicon