title: PEGylated silica nanoparticles encapsulating multiple magnetite nanocrystals for high-performance microscopic magnetic resonance angiography.
abstract: A novel magnetic resonance (MR) angiographic method, 3DΔR2-mMRA (three dimensional and ΔR2 based microscopy magnetic resonance angiography), is developed as a clinical diagnosis for depicting the function and structure of cerebral small vessels. However, the visibility of microvasculatures and the precision of cerebral blood volume calculation greatly rely on the transverse relaxivity and intravascular half-life of contrast agent, respectively. In this work, we report a blood pool contrast agent named H-Fe₃O₄@SiO₂-PEG where multiple Fe₃O₄ nanocrystals are encapsulated in a thin silica shell to enhance the T₂-relaxivity (r₂ = 342.8 mM⁻¹ s⁻¹) and poly(ethylene glycol) (PEG) is employed to reduce opsonization and prolong circulation time of nanoparticles. Utilization of the newly developed H-Fe₃O₄@SiO₂-PEG with a novel MR angiographic methodology, a high-resolution MR image of rat cerebral microvasculatures is successfully obtained.
authors.affiliation: Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan.
authors.forename: Si-Han
authors.initials: SH
authors.lastname: Wu
authors.forename: Chien-Yuan
authors.initials: CY
authors.lastname: Lin
authors.forename: Yann
authors.initials: Y
authors.lastname: Hung
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Chen
authors.initials: C
authors.lastname: Chang
authors.forename: Chung-Yuan
authors.initials: CY
authors.lastname: Mou
mesh_terms: D000818:Animals; D002560:Cerebrovascular Circulation; D003911:Dextrans / Q000737:chemistry; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000295:instrumentation* / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000737:chemistry; D008422:Materials Testing; D051379:Mice; D055806:Microvessels / Q000648:ultrastructure; D053758:Nanoparticles / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D051381:Rats; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D003911:Dextrans; D058185:Magnetite Nanoparticles; D011092:Polyethylene Glycols; D012822:Silicon Dioxide; C065507:ferumoxides; D052203:Ferrosoferric Oxide