The first two authors contributed equally.
Targeted RGD nanoparticles for highly sensitive in vivo integrin receptor imaging
Article first published online: 30 JAN 2012
Copyright © 2012 John Wiley & Sons, Ltd.
Contrast Media & Molecular Imaging
Volume 7, Issue 1, pages 7–18, January/February 2012
How to Cite
Lin, R.-Y., Dayananda, K., Chen, T.-J., Chen, C.-Y., Liu, G.-C., Lin, K.-L. and Wang, Y.-M. (2012), Targeted RGD nanoparticles for highly sensitive in vivo integrin receptor imaging. Contrast Media Mol Imaging, 7: 7–18. doi: 10.1002/cmmi.457
- Issue published online: 30 JAN 2012
- Article first published online: 30 JAN 2012
- Manuscript Accepted: 16 MAY 2011
- Manuscript Revised: 14 MAR 2011
- Manuscript Received: 6 SEP 2010
- superparamagnetic nanoparticles (SPIO);
- magnetic resonance imaging (MRI);
A new magnetic resonance imaging (MRI) contrast bearing RGD peptide is reported. In this study, ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles with various sizes were prepared. Particles sizes between 6 and 13 nm were tuned by varying the stirring rate. Remarkable negative contrast was observed because USPIO nanoparticles (13.1 ± 2.1 nm) generated high transversal relaxivity r2 (188 ± 3 m m−1 s−1) and saturation magnetization (94 emu g−1 Fe). The USPIO nanoparticles were coated with PDA [2-(pyridyldithio)-ethylamine; PDA nanoparticles] containing functional polymer, which can be readily synthesized by Michael addition. The PDA nanoparticles were conjugated with RGD peptide (RGD nanoparticles) for targeting the specific site. The target specificity and high relaxivity allowed RGD nanoparticles to differentiate the expression level of integrin receptor on several cell lines and tumors (MCF-7, A-549, HT-29 and HT-1080) by in vitro and in vivo MR imaging. Importantly, a remarkable negative contrast (−51.3 ± 6.7%) was observed for in vivo MR imaging of MCF-7 tumor. This result implies that the RGD nanoparticles that greatly enhance the MR imaging are highly sensitive for early stage tumor detection. Copyright © 2012 John Wiley & Sons, Ltd.