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Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles
Published on: October 19, 2015
pH-Sensitive Magnetite Nanoparticles Modified with Hyperbranched Polymers and Folic Acid for Targeted Imaging and
Seyed Jamal Tabatabaei Rezaei1, Asemeh Mashhadi Malekzadeh1, Ali Ramazani1
1Laboratory of novel drug delivery systems, Department of Chemistry, Faculty of Science, University of Zanjan, P.O. Box 45195-313, Zanjan, Iran.
Objective:
A novel pH-sensitive superparamagnetic drug delivery system was developed based on quercetin loaded hyperbranched polyamidoamine-b-polyethylene glycol-folic acid-modified Fe3O4 nanoparticles (Fe3O4@PAMAM-b-PEG-FA).
Methods:
The nanoparticles exhibit excellent water dispersity with well-defined size distribution (around 51.8 nm) and strong magnetisability. In vitro release studies demonstrated that the quercetinloaded Fe3O4@PAMAM-b-PEG-FA nanoparticles are stable at normal physiologic conditions (pH 7.4 and 37°C) but sensitive to acidic conditions (pH 5.6 and 37°C), which led to the rapid release of the loaded drug.
Results:
Fluorescent microscopy results indicated that the Fe3O4@PAMAM-b-PEG-FA nanoparticles could be efficiently accumulated in tumor tissue compared with non-folate conjugated nanoparticles. Also, in comparison with free quercetin, the quercetin loaded Fe3O4@PAMAM-b-PEG-FA exerts higher cytotoxicity. Furthermore, this magnetic nanocarrier showed high MRI sensitivity, even in its lower iron content.
Conclusion:
The results indicated that the prepared nanoparticles are an effective chemotherapy and diagnosis system to inhibit proliferation and monitor the progression of tumor cells, respectively.

