title: Multifunctional upconversion mesoporous silica nanostructures for dual modal imaging and in vivo drug delivery.
abstract: Incorporating the agents for magnetic resonance imaging (MRI), optical imaging, and therapy in one nanostructured matrix to construct multifunctional nanomedical platform has attracted great attention for simultaneous diagnostic and therapeutic applications. In this work, a facile methodology is developed to construct a multifunctional anticancer drug nanocarrier by combining the special advantages of upconversion nanoparticles and mesoporous silica. β-NaYF4 :Yb(3+) , Er(3+) @β-NaGdF4 :Yb(3+) is chosen as it can provide the dual modality of upconversion luminescence and MRI. Then mesoporous silica is directly coated onto the upconversion nanoparticles to form discrete, monodisperse, highly uniform, and core-shell structured nanospheres (labeled as UCNPs@mSiO2 ), which are subsequently functionalized with hydrophilic polymer poly(ethylene glycol) (PEG) to improve the colloidal stability and biocompatibility. The obtained multifunctional nanocomposites can be used as an anticancer drug delivery carrier and applied for imaging. The anticancer drug doxorubicin (DOX) is absorbed into UCNPs@mSiO2 -PEG nanospheres and released in a pH-sensitive pattern. In vitro cell cytotoxicity tests on cancer cells verify that the DOX-loaded UCNPs@mSiO2 -PEG has comparable cytotoxicity with free DOX at the same concentration of DOX. In addition, the T1 -weighted MRI that measures in aqueous solutions reveals that the contrast brightening increases with the concentration of Gd(3+) component. Upconversion luminescence images of UCNPs@mSiO2 -PEG uptaken by cells show green emission under 980 nm infrared laser excitation. Finally, the nanocomposites show low systematic toxicity and high in vivo antitumor therapy efficacy. These findings highlight the fascinating features of upconversion-mesoporous nanocomposites as multimodality imaging contrast agents and nanocarrier for drug molecules.
authors.affiliation: State Key Laboratory of Rare Earth, Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.
authors.forename: Chunxia
authors.initials: C
authors.lastname: Li
authors.forename: Dongmei
authors.initials: D
authors.lastname: Yang
authors.forename: Ping'an
authors.initials: P
authors.lastname: Ma
authors.forename: Yinyin
authors.initials: Y
authors.lastname: Chen
authors.forename: Yuan
authors.initials: Y
authors.lastname: Wu
authors.forename: Zhiyou
authors.initials: Z
authors.lastname: Hou
authors.forename: Yunlu
authors.initials: Y
authors.lastname: Dai
authors.forename: Jihong
authors.initials: J
authors.lastname: Zhao
authors.forename: Changping
authors.initials: C
authors.lastname: Sui
authors.forename: Jun
authors.initials: J
authors.lastname: Lin
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry; D045744:Cell Line, Tumor; D003102:Colloids / Q000737:chemistry; D004317:Doxorubicin / Q000008:administration & dosage; D016503:Drug Delivery Systems; D005682:Gadolinium / Q000737:chemistry; D006367:HeLa Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007834:Lasers; D049449:Luminescence; D008279:Magnetic Resonance Imaging; D008280:Magnetics; D051379:Mice; D046529:Microscopy, Electron, Transmission; D050997:Nanomedicine; D054118:Nanospheres / Q000737:chemistry; D049329:Nanostructures / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D000970:Antineoplastic Agents; D001672:Biocompatible Materials; D003102:Colloids; D011108:Polymers; D011092:Polyethylene Glycols; D012822:Silicon Dioxide; D004317:Doxorubicin; D005682:Gadolinium
keywords: drug delivery; magnetic resonance imaging; upconversion cell imaging; upconversion mesoporous silica