Aptamer-modified magnetic nanoprobe for molecular MR imaging of VEGFR2 on angiogenic vasculature
1 Department of Chemical and Biomolecular Engineering, College of Engineering, Yonsei University, Seoul 120-749, Republic of Korea
2 Department of Radiology, College of Medicine, Yonsei University, Seoul 120-752, Republic of Korea
3 POSTECH Aptamer Initiative Program, Division of Integrative Bioscience and Biotechnology, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea
Nanoscale Research Letters 2013, 8:399 doi:10.1186/1556-276X-8-399Published: 26 September 2013
Nucleic acid-based aptamers have been developed for the specific delivery of diagnostic nanoprobes. Here, we introduce a new class of smart imaging nanoprobe, which is based on hybridization of a magnetic nanocrystal with a specific aptamer for specific detection of the angiogenic vasculature of glioblastoma via magnetic resonance (MR) imaging. The magnetic nanocrystal imaging core was synthesized using the thermal decomposition method and enveloped by carboxyl polysorbate 80 for water solubilization and conjugation of the targeting moiety. Subsequently, the surface of the carboxylated magnetic nanocrystal was modified with amine-functionalized aptamers that specifically bind to the vascular growth factor receptor 2 (VEGFR2) that is overexpressed on angiogenic vessels. To assess the targeted imaging potential of the aptamer-conjugated magnetic nanocrystal for VEGFR2 markers, the magnetic properties and MR imaging sensitivity were investigated using the orthotopic glioblastoma mouse model. In in vivo tests, the aptamer-conjugated magnetic nanocrystal effectively targeted VEGFR2 and demonstrated excellent MR imaging sensitivity with no cytotoxicity.