Fluorescent Dye Labeled Iron Oxide/Silica Core/Shell Nanoparticle as a Multimodal Imaging Probe
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To develop an MRI/optical multimodal imaging probe based on dye-conjugated iron oxide/silica core/shell nanoparticle, and investigate the distance-dependent fluorescence quenching through careful control of the distance between the iron oxide core and fluorescent dyes.
Different size of core/shell nanoparticles were prepared by varying the silica shell width. PEGylation on the surface of silica shell was followed to improve the stability of particles in the physiological condition. In vitro cytotoxicity was evaluated by the MTT assay on a HeLa cell line and in vivo imaging of subcutaneous SCC7 xenografted mice was performed using MRI/optical imaging modalities.
Diameter and ζ-potential of the nanoparticles were measured, and TEM images demonstrated the mono-disperse nature of the particles. Quenching efficiency of the dyes on the surface was nearly 100% in the smallest nanoparticle, while almost no quenching effect was observed for the largest nanoparticle. In vitro cytotoxicity showed nearly 90% cell viability at 0.15 Fe mg/mL, a comparable concentration for clinical use. The tumor area was significantly darkened after the nanoparticle injection due to the high transverse relaxivity value of the nanoparticles. Fluorescence signal was affected by the particle size due to the distance-dependent quenching/dequenching behaviour.
Key WordsCore-shell nanoparticle Fluorescence quenching Iron oxide Multimodal imaging probe Optical imaging
Dulbecco’s modified eagle medium
Ethyl (dimethylaminopropyl) carbodiimide
Fetal bovine serum
Fluorescence resonance energy transfer
Inductively coupled plasma mass spectrometry
Methoxy poly (ethylene glycol) mono acid
Magnetic resonance imaging
Transmission electron microscopy
Acknowledgments and Disclosures
This study was supported by a grant from Basic Science Research Program (grant no. 2010–0027955) of MEST and National Research Foundation of Korea (grant no. 2010–0023581). C.-H. Ahn appreciate LG Yonam Foundation for the support.
- 25.Chen F, Bu W, Chen Y, Fan Y, He Q, Zhu M, et al. A Sub-50 nm Monosized Superparamagnetic Fe3O4@SiO2T2-Weighted MRI Contrast Agent: Highly Reproducible Synthesis of Uniform Single-Loaded Core–Shell Nanostructures. Chemistry – An Asian. Journal. 2009;4(12):1809–16.Google Scholar