title: Core-shell NaYF4:Yb3+,Tm3+@FexOy nanocrystals for dual-modality T2-enhanced magnetic resonance and NIR-to-NIR upconversion luminescent imaging of small-animal lymphatic node.
abstract: New core-shell structured NaYF(4):Yb(3+),Tm(3+)@Fe(x)O(y) nanocrystals, with 20 nm Yb(3+),Tm(3+)-co-doped NaYF(4) nanocrystals as a core and 5 nm Fe(x)O(y) nanocrystals as a shell, have been synthesized and characterized by TEM and XRD analysis. These core-shell nanocrystals exhibit excellent near-infrared upconversion luminescence (UCL) emission at 800 nm under excitation by a continuous-wave 980 nm laser and superparamagnetic properties with a saturation magnetization (Ms) of ∼12 emu/g. Water-soluble nanocrystals were obtained by surface ligand exchange of oleic acid-coated precursor nanocrystals, and their internalization within living cells has been investigated by laser scanning UCL microscopy. Furthermore, the obtained core-shell nanocrystals have been applied in dual-modality T(2)-enhanced magnetic resonance (MR) and UCL imaging in vivo of the lymphatic system. Moreover, the toxicity of NaYF(4):Yb(3+),Tm(3+)@Fe(x)O(y) nanocrystals has also been evaluated by MTT assay, IC50 values, and histological analysis of lymphatic node sections.
authors: Advanced Materials Laboratory & Department of Chemistry, Fudan University, Shanghai, PR China.
authors: Ao
authors: A
authors: Xia
authors: Yuan
authors: Y
authors: Gao
authors: Jing
authors: J
authors: Zhou
authors: Chunyan
authors: C
authors: Li
authors: Tianshe
authors: T
authors: Yang
authors: Dongmei
authors: D
authors: Wu
authors: Limin
authors: L
authors: Wu
authors: Fuyou
authors: F
authors: Li
mesh_terms: D000818:Animals; D002460:Cell Line; D003952:Diagnostic Imaging / Q000379:methods; D005290:Ferric Compounds / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry*; D006801:Humans; D007834:Lasers; D008163:Luminescent Measurements / Q000379:methods*; D008198:Lymph Nodes / Q000033:anatomy & histology* / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D008422:Materials Testing; D051379:Mice; D008819:Mice, Nude; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley; D013635:Tantalum / Q000737:chemistry*; D015018:Ytterbium / Q000737:chemistry*; D015019:Yttrium / Q000737:chemistry*
chemical_list: D005290:Ferric Compounds; C525362:sodium yttriumtetrafluoride; C000499:ferric oxide; D015019:Yttrium; D013635:Tantalum; D015018:Ytterbium; D005459:Fluorides