title: Superparamagnetic maghemite nanoparticles from solid-state synthesis - their functionalization towards peroral MRI contrast agent and magnetic carrier for trypsin immobilization.
abstract: Nearly monodispersed superparamagnetic maghemite nanoparticles (15-20nm) were prepared by a one-step thermal decomposition of iron(II) acetate in air at 400 degrees C. The presented synthetic route is simple, cost effective and allows to prepare the high-quality superparamagnetic particles in a large scale. The as-prepared particles were exploited for the development of magnetic nanocomposites with the possible applicability in medicine and biochemistry. For the purposes of the MRI diagnostics, the maghemite particles were simply dispersed in the bentonite matrix. The resulting nanocomposite represents very effective and cheap oral negative contrast agent for MRI of the gastrointestinal tract and reveals excellent contrast properties, fully comparable with those obtained for commercial contrast material. The results of the clinical research of this maghemite-bentonite contrast agent for imaging of the small bowel are discussed. For biochemical applications, the primary functionalization of the prepared maghemite nanoparticles with chitosan was performed. In this way, a highly efficient magnetic carrier for protein immobilization was obtained as demonstrated by conjugating thermostable raffinose-modified trypsin (RMT) using glutaraldehyde. The covalent conjugation resulted in a further increase in trypsin thermostability (T(50)=61 degrees C) and elimination of its autolysis. Consequently, the immobilization of RMT allowed fast in-solution digestion of proteins and their identification by MALDI-TOF mass spectrometry.
authors.affiliation: Department of Physical Chemistry, Palacky University, Olomouc, Czech Republic.
authors.forename: Katerina
authors.initials: K
authors.lastname: Kluchova
authors.forename: Radek
authors.initials: R
authors.lastname: Zboril
authors.forename: Jiri
authors.initials: J
authors.lastname: Tucek
authors.forename: Michaela
authors.initials: M
authors.lastname: Pecova
authors.forename: Ludmila
authors.initials: L
authors.lastname: Zajoncova
authors.forename: Ivo
authors.initials: I
authors.lastname: Safarik
authors.forename: Miroslav
authors.initials: M
authors.lastname: Mashlan
authors.forename: Ingrid
authors.initials: I
authors.lastname: Markova
authors.forename: Dalibor
authors.initials: D
authors.lastname: Jancik
authors.forename: Marek
authors.initials: M
authors.lastname: Sebela
authors.forename: Helena
authors.initials: H
authors.lastname: Bartonkova
authors.forename: Vassiliki
authors.initials: V
authors.lastname: Bellesi
authors.forename: Pavel
authors.initials: P
authors.lastname: Novak
authors.forename: Dimitris
authors.initials: D
authors.lastname: Petridis
mesh_terms: D003287:Contrast Media; D004800:Enzymes, Immobilized; D005290:Ferric Compounds; D041981:Gastrointestinal Tract / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D014357:Trypsin; D014961:X-Ray Diffraction
chemical_list: D003287:Contrast Media; D004800:Enzymes, Immobilized; D005290:Ferric Compounds; C000499:ferric oxide; D014357:Trypsin