title: Activatable fluorescence/MRI bimodal platform for tumor cell imaging via MnO2 nanosheet-aptamer nanoprobe.
abstract: A novel dual-activatable fluorescence/MRI bimodal platform is designed for tumor cell imaging by using a redoxable manganese dioxide (MnO2) nanosheet-aptamer nanoprobe. The redoxable MnO2 nanosheet acts as a DNA nanocarrier, fluorescence quencher, and intracellular glutathione (GSH)-activated MRI contrast agent. In the absence of target cells, neither fluorescence signaling nor MRI contrast of the nanoprobe is activated. In the presence of target cells, the binding of aptamers to their targets weakens the adsorption of aptamers on the MnO2 nanosheets, causing partial fluorescence recovery, illuminating the target cells, and also facilitating the endocytosis of nanoprobes into target cells. After endocytosis, the reduction of MnO2 nanosheets by GSH further activates the fluorescence signals and generates large amounts of Mn(2+) ions suitable for MRI. This platform should facilitate the development of various dual-activatable fluorescence/MRI bimodalities for use in cells or in vivo.
authors: Molecular Science and Biomedicine Laboratory, State Key Laboratory for Chemo/Bio Sensing and Chemometrics, College of Chemistry and Chemical Engineering, College of Biology, and Collaborative Research Center of Molecular Engineering for Theranostics, Hunan University , Changsha 410082, China.
authors: Zilong
authors: Z
authors: Zhao
authors: Huanhuan
authors: H
authors: Fan
authors: Gaofeng
authors: G
authors: Zhou
authors: Huarong
authors: H
authors: Bai
authors: Hao
authors: H
authors: Liang
authors: Ruowen
authors: R
authors: Wang
authors: Xiaobing
authors: X
authors: Zhang
authors: Weihong
authors: W
authors: Tan
mesh_terms: D000327:Adsorption; D045744:Cell Line, Tumor; D003287:Contrast Media / Q000737:chemistry; D004247:DNA / Q000737:chemistry; D004705:Endocytosis; D005456:Fluorescent Dyes / Q000737:chemistry*; D005978:Glutathione / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D007477:Ions; D008024:Ligands; D008279:Magnetic Resonance Imaging; D008345:Manganese / Q000737:chemistry; D017895:Manganese Compounds / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D049329:Nanostructures / Q000737:chemistry*; D009369:Neoplasms / Q000473:pathology*; D010087:Oxides / Q000737:chemistry*
chemical_list: D003287:Contrast Media; D005456:Fluorescent Dyes; D007477:Ions; D008024:Ligands; D017895:Manganese Compounds; D010087:Oxides; D008345:Manganese; D004247:DNA; D005978:Glutathione; C016552:manganese dioxide