title: Activatable molecular MRI nanoprobe for tumor cell imaging based on gadolinium oxide and iron oxide nanoparticle.
abstract: Activatable molecular MRI nanoprobe for intracellular GSH sensing was designed. As an alternative to "always on" nanoprobe, activatable imaging nanoprobes which are designed to amplify or boost imaging signals only in response to the targets have attracted more and more attention. In this paper, we designed a novel activatable molecular magnetic resonance imaging (MRI) nanoprobe for tumor cell recognization based on a MRI signal variation induced by the distance change between T1 and T2 contrast agents (CAs) in the presence of glutathione (GSH). To achieve this aim, carboxyl group functionalized iron oxide nanoparticles (Fe3O4 NPs) and polyethylene glycol-coated gadolinium oxide (PEG-Gd2O3) NPs as T2 and T1 MRI CA were connected by cystamine which contains a disulfide linkage. Transmission electron microscopic (TEM), X-ray photoelectron spectroscopy (XPS), energy dispersive spectrometer (EDS), fourier transform infrared spectroscopy (FT-IR), mass spectra and (1)H nuclear magnetic resonance spectroscopy ((1)H NMR) were introduced for their characterizations. The formation of Fe3O4-cystamine-Gd2O3 (Fe3O4-SS-Gd2O3) nanocomplex resulted in a quenched T1 signal due to the near proximity of PEG-Gd2O3 NPs to Fe3O4 NPs and a "light-up" T1 signal with the cleavage of disulfide bond in the presence of GSH. These results provide not only an easy way to realize MRI of tumor cells based on the overexpressed intracellular GSH level, but also a new insight for the design of activatable MRI nanoprobe.
authors: Department of Radiology, Affiliated Hospital of Xuzhou Medical College, Xuzhou 221006, China; School of Medical Imaging, Xuzhou Medical University, Xuzhou 221004, China.
authors: Jingjing
authors: J
authors: Li
authors: School of Medical Imaging, Xuzhou Medical University, Xuzhou 221004, China.
authors: Shan
authors: S
authors: Wang
authors: School of Medical Imaging, Xuzhou Medical University, Xuzhou 221004, China.
authors: Chen
authors: C
authors: Wu
authors: School of Medical Imaging, Xuzhou Medical University, Xuzhou 221004, China.
authors: Yue
authors: Y
authors: Dai
authors: Jiangsu Key Laboratory of Biological Cancer Therapy, Xuzhou Medical University, Xuzhou 221004, China; Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy, Cancer Institute, Xuzhou Medical University, Xuzhou 221004, China.
authors: Pingfu
authors: P
authors: Hou
authors: Department of Radiology, Affiliated Hospital of Xuzhou Medical College, Xuzhou 221006, China; School of Medical Imaging, Xuzhou Medical University, Xuzhou 221004, China.
authors: Cuiping
authors: C
authors: Han
authors: Department of Radiology, Affiliated Hospital of Xuzhou Medical College, Xuzhou 221006, China; School of Medical Imaging, Xuzhou Medical University, Xuzhou 221004, China. Electronic address: xkpaper@163.com.
authors: Kai
authors: K
authors: Xu
mesh_terms: D000818:Animals; D058948:Cell Tracking / Q000379:methods*; D003287:Contrast Media / Q000138:chemical synthesis; D005682:Gadolinium / Q000737:chemistry*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D051379:Mice; D015336:Molecular Probe Techniques; D015335:Molecular Probes / Q000737:chemistry; D009374:Neoplasms, Experimental / Q000000981:diagnostic imaging* / Q000473:pathology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D058185:Magnetite Nanoparticles; D015335:Molecular Probes; C030581:gadolinium oxide; D005682:Gadolinium
keywords: Activatable nanoprobe; Aptamer; Contrast agent; Glutathione; Magnetic resonance imaging