Release activation of iron oxide nanoparticles: (REACTION) A novel environmentally sensitive MRI paradigm

Dorit Granot, Erik M. Shapiro

Research output: Contribution to journalArticle

  • 11 Citations

Abstract

Smart contrast agents for MRI-based cell tracking would enable the use of MRI methodologies to not only detect the location of cells but also gene expression. Here, we report on a new enzyme/contrast agent paradigm which involves the enzymatic degradation of the polymer coating of magnetic nanoparticles to release encapsulated magnetic cores. Cells were labeled with particles coated with a polymer, which is cleavable by a specific enzyme. This coat restricts the approach of water to the particle, preventing the magnetic core from efficiently relaxing protons. The reactive enzyme was delivered to cells and changes in cellular T2 and T2* relaxation times of ∼ 35% and ∼ 50% were achieved in vitro. Large enhancements of dark contrast volume (240%) and contrast-to-noise ratio (48%) within the contrast regions were measured, in vivo, for cells co-labeled with enzyme and particles. These results warrant exploration of genetic avenues toward achieving release activation of iron oxide nanoparticles. Magn Reson Med, 2011.

Original languageEnglish (US)
Pages (from-to)1253-1259
Number of pages7
JournalMagnetic Resonance in Medicine
Volume65
Issue number5
DOIs
StatePublished - May 2011
Externally publishedYes

Profile

Nanoparticles
Oxides
Iron
Enzymes
Contrast Media
Polymers
Cell Tracking
Noise
Protons
Gene Expression
Water
In Vitro Techniques

Keywords

  • cells
  • contrast agents
  • iron oxide
  • MRI
  • nanoparticles

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging

Cite this

Release activation of iron oxide nanoparticles : (REACTION) A novel environmentally sensitive MRI paradigm. / Granot, Dorit; Shapiro, Erik M.

In: Magnetic Resonance in Medicine, Vol. 65, No. 5, 05.2011, p. 1253-1259.

Research output: Contribution to journalArticle

Granot, Dorit; Shapiro, Erik M. / Release activation of iron oxide nanoparticles : (REACTION) A novel environmentally sensitive MRI paradigm.

In: Magnetic Resonance in Medicine, Vol. 65, No. 5, 05.2011, p. 1253-1259.

Research output: Contribution to journalArticle

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