title: Accumulation of magnetic iron oxide nanoparticles coated with variably sized polyethylene glycol in murine tumors.
abstract: Iron oxide nanoparticles have found widespread applications in different areas including cell separation, drug delivery and as contrast agents. Due to water insolubility and stability issues, nanoparticles utilized for biological applications require coatings such as the commonly employed polyethylene glycol (PEG). Despite its frequent use, the influence of PEG coatings on the physicochemical and biological properties of iron nanoparticles has hitherto not been studied in detail. To address this, we studied the effect of 333-20,000 Da PEG coatings that resulted in larger hydrodynamic size, lower surface charge, longer circulation half-life, and lower uptake in macrophage cells when the particles were coated with high molecular weight (M(w)) PEG molecules. By use of magnetic resonance imaging, we show coating-dependent in vivo uptake in murine tumors with an optimal coating M(w) of 10,000 Da.
authors.affiliation: Interdisciplinary Nanoscience Center (iNANO), Departments of Molecular Biology, Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark.
authors.forename: Esben Kjær Unmack
authors.initials: EK
authors.lastname: Larsen
authors.forename: Thomas
authors.initials: T
authors.lastname: Nielsen
authors.forename: Thomas
authors.initials: T
authors.lastname: Wittenborn
authors.forename: Louise Munk
authors.initials: LM
authors.lastname: Rydtoft
authors.forename: Arcot R
authors.initials: AR
authors.lastname: Lokanathan
authors.forename: Line
authors.initials: L
authors.lastname: Hansen
authors.forename: Leif
authors.initials: L
authors.lastname: Østergaard
authors.forename: Peter
authors.initials: P
authors.lastname: Kingshott
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Howard
authors.forename: Flemming
authors.initials: F
authors.lastname: Besenbacher
authors.forename: Niels Chr
authors.initials: NC
authors.lastname: Nielsen
authors.forename: Jørgen
authors.initials: J
authors.lastname: Kjems
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000493:pharmacokinetics*; D003287:Contrast Media / Q000737:chemistry / Q000493:pharmacokinetics; D016503:Drug Delivery Systems; D005290:Ferric Compounds / Q000737:chemistry / Q000493:pharmacokinetics*; D008280:Magnetics; D053768:Metal Nanoparticles / Q000737:chemistry; D051379:Mice; D008809:Mice, Inbred C3H; D008954:Models, Biological; D008970:Molecular Weight; D009369:Neoplasms / Q000175:diagnosis / Q000378:metabolism* / Q000473:pathology; D019301:Oleic Acid / Q000737:chemistry / Q000493:pharmacokinetics; D010316:Particle Size; D011092:Polyethylene Glycols / Q000737:chemistry / Q000493:pharmacokinetics*; D012821:Silanes / Q000737:chemistry / Q000493:pharmacokinetics; D014018:Tissue Distribution
chemical_list: D020099:Coated Materials, Biocompatible; D003287:Contrast Media; D005290:Ferric Compounds; D012821:Silanes; C000499:ferric oxide; D019301:Oleic Acid; D011092:Polyethylene Glycols