title: Geometrically confined ultrasmall gadolinium oxide nanoparticles boost the T(1) contrast ability.
abstract: High-performance magnetic resonance imaging (MRI) contrast agents and novel contrast enhancement strategies are urgently needed for sensitive and accurate diagnosis. Here we report a strategy to construct a new T1 contrast agent based on the Solomon-Bloembergen-Morgan (SBM) theory. We loaded the ultrasmall gadolinium oxide nanoparticles into worm-like interior channels of mesoporous silica nanospheres (Gd2O3@MSN nanocomposites). This unique structure endows the nanocomposites with geometrical confinement, high molecular tumbling time, and a large coordinated number of water molecules, which results in a significant enhancement of the T1 contrast with longitudinal proton relaxivity (r1) as high as 45.08 mM(-1) s(-1). Such a high r1 value of Gd2O3@MSN, compared to those of ultrasmall Gd2O3 nanoparticles and gadolinium-based clinical contrast agents, is mainly attributed to the strong geometrical confinement effect. This strategy provides new guidance for developing various high-performance T1 contrast agents for sensitive imaging and disease diagnosis.
authors.affiliation: State Key Laboratory of Physical Chemistry of Solid Surfaces, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, The Key Laboratory for Chemical Biology of Fujian Province, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China. jhgao@xmu.edu.cn.
authors.forename: Kaiyuan
authors.initials: K
authors.lastname: Ni
authors.forename: Zhenghuan
authors.initials: Z
authors.lastname: Zhao
authors.forename: Zongjun
authors.initials: Z
authors.lastname: Zhang
authors.forename: Zijian
authors.initials: Z
authors.lastname: Zhou
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.forename: Lirong
authors.initials: L
authors.lastname: Wang
authors.forename: Hua
authors.initials: H
authors.lastname: Ai
authors.forename: Jinhao
authors.initials: J
authors.lastname: Gao
mesh_terms: D003287:Contrast Media / Q000737:chemistry / Q000494:pharmacology; D005682:Gadolinium / Q000737:chemistry / Q000494:pharmacology; D056945:Hep G2 Cells; D006801:Humans; D008279:Magnetic Resonance Imaging; D008422:Materials Testing; D053761:Nanocomposites / Q000737:chemistry*; D010316:Particle Size; D012822:Silicon Dioxide / Q000737:chemistry / Q000494:pharmacology
chemical_list: D003287:Contrast Media; D012822:Silicon Dioxide; D005682:Gadolinium