title: Engineered iron-oxide-based nanoparticles as enhanced T1 contrast agents for efficient tumor imaging.
abstract: We report the design and synthesis of small-sized zwitterion-coated gadolinium-embedded iron oxide (GdIO) nanoparticles, which exhibit a strong T1 contrast effect for tumor imaging through enhanced permeation and retention effect and the ability to clear out of the body in living subjects. The combination of spin-canting effects and the collection of gadolinium species within small-sized GdIO nanoparticles led to a significantly enhanced T1 contrast effect. For example, GdIO nanoparticles with a diameter of ∼4.8 nm exhibited a high r1 relaxivity of 7.85 mM(-1)·S(-1) and a low r2/r1 ratio of 5.24. After being coated with zwitterionic dopamine sulfonate molecules, the 4.8 nm GdIO nanoparticles showed a steady hydrodynamic diameter (∼5.2 nm) in both PBS buffer and fetal bovine serum solution, indicating a low nonspecific protein absorption. This study provides a valuable strategy for the design of highly sensitive iron-oxide-based T1 contrast agents with relatively long circulation half-lives (∼50 min), efficient tumor passive targeting (SKOV3, human ovarian cancer xenograft tumor as a model), and the possibility of rapid renal clearance after tumor imaging.
authors.affiliation: State Key Laboratory of Physical Chemistry of Solid Surfaces, 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.
authors.forename: Zijian
authors.initials: Z
authors.lastname: Zhou
authors.forename: Lirong
authors.initials: L
authors.lastname: Wang
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Chi
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Bao
authors.forename: Lijiao
authors.initials: L
authors.lastname: Yang
authors.forename: Wenxiu
authors.initials: W
authors.lastname: Zhao
authors.forename: Zhong
authors.initials: Z
authors.lastname: Chen
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Wang
authors.forename: Xiaoyuan
authors.initials: X
authors.lastname: Chen
authors.forename: Jinhao
authors.initials: J
authors.lastname: Gao
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D003287:Contrast Media / Q000138:chemical synthesis*; D005260:Female; D005682:Gadolinium / Q000737:chemistry; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000737:chemistry; D051379:Mice; D053769:Nanocapsules / Q000737:chemistry; D010051:Ovarian Neoplasms / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D058185:Magnetite Nanoparticles; D053769:Nanocapsules; D005682:Gadolinium