title: (Carboxymethyl)chitosan-modified superparamagnetic iron oxide nanoparticles for magnetic resonance imaging of stem cells.
abstract: Magnetic resonance imaging (MRI) is emerging as a powerful tool for in vivo noninvasive tracking of magnetically labeled stem cells. In this work, we present an efficient cell-labeling approach using (carboxymethyl)chitosan-modified superparamagnetic iron oxide nanoparticles (CMCS-SPIONs) as contrast agent in MRI. The CMCS-SPIONs were prepared by conjugating (carboxymethyl)chitosan to (3-aminopropyl)trimethoxysilane-treated SPIONs. These nanoparticles were internalized into human mesenchymal stem cells (hMSCs) via endocytosis as confirmed by Prussian Blue staining and electron microscopy investigation and quantified by inductively coupled plasma mass spectrometry. A MTT assay of the labeled cells showed that CMCS-SPIONs did not possess significant cytotoxicity. In addition, the osteogenic and adipogenic differentiations of the hMSCs were not influenced by the labeling process. The in vitro detection threshold of cells after incubation with 0.05 mg/mL of CMCS-SPIONs for 24 h was estimated to be about 40 cells. The results from this study indicate that the biocompatible CMCS-SPIONs show promise for use with MRI in visualizing hMSCs.
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, Kent Ridge, Singapore, Singapore.
authors.forename: Zhilong
authors.initials: Z
authors.lastname: Shi
authors.forename: K G
authors.initials: KG
authors.lastname: Neoh
authors.forename: E T
authors.initials: ET
authors.lastname: Kang
authors.forename: Borys
authors.initials: B
authors.lastname: Shuter
authors.forename: Shih-Chang
authors.initials: SC
authors.lastname: Wang
authors.forename: Chyekhoon
authors.initials: C
authors.lastname: Poh
authors.forename: W
authors.initials: W
authors.lastname: Wang
mesh_terms: D000704:Analysis of Variance; D002454:Cell Differentiation; D002470:Cell Survival; D002478:Cells, Cultured; D048271:Chitosan / Q000031:analogs & derivatives* / Q000737:chemistry; D003287:Contrast Media / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D056951:Photoelectron Spectroscopy
chemical_list: D003287:Contrast Media; D005290:Ferric Compounds; C514968:carboxymethyl-chitosan; C000499:ferric oxide; D048271:Chitosan