title: Aqueous stabilisation of carbon-encapsulated superparamagnetic α-iron nanoparticles for biomedical applications.
abstract: Carbon-based nanomaterials, such as carbon-encapsulated magnetic nanoparticles (CEMNP, core@shell), show a wide range of desirable properties for applications in the biomedical field (clinical MRI, hyperthermia), for energy production and storage (hydrogen storage), for the improvement of electronic components and for environmental applications (water-treatment). However, this kind of nanoparticle tends to aggregate in water suspensions. This often hampers the processability of the suspensions and presents an obstacle to their application in many fields. Here the stabilisation of core-shell Fe-C nanoparticles by surface adsorbed polyvinyl-alcohol (PVA) is presented. Different PVA/CEMNP mass ratios (9, 36, 144 and 576 w/w) were studied. Several characterisation techniques were used in order to determine the size distribution of the particles and to optimize the PVA/CEMNP ratio. A good colloidal stability was obtained for spherical nanoparticles about 50 nm in diameter containing several superparamagnetic Fe cores. The nanoparticles were found to be isolated and well dispersed in solution. The use of PVA for coating carbon-encapsulated Fe nanoparticles does not only result in a good colloidal stability in aqueous suspensions, but the resulting particles also show low cytotoxicity and an interesting cell internalization behaviour. The simple stabilization method developed here can likely be extended to other core@shell nanoparticle systems as well as other carbon-based nanomaterials in the future.
authors.affiliation: FEMAN Group, IN2 UB, Department of Applied Physics and Optics, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Catalonia, Spain. noeaguilo@gmail.com noemiaguilo@ub.edu.
authors.forename: Noemí
authors.initials: N
authors.lastname: Aguiló-Aguayo
authors.forename: Lionel
authors.initials: L
authors.lastname: Maurizi
authors.forename: Sandra
authors.initials: S
authors.lastname: Galmarini
authors.forename: Marie Gabrielle
authors.initials: MG
authors.lastname: Ollivier-Beuzelin
authors.forename: Géraldine
authors.initials: G
authors.lastname: Coullerez
authors.forename: Enric
authors.initials: E
authors.lastname: Bertran
authors.forename: Heinrich
authors.initials: H
authors.lastname: Hofmann
mesh_terms: D002244:Carbon / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D057446:Hydrodynamics; D007501:Iron / Q000737:chemistry*; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000633:toxicity / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D011142:Polyvinyl Alcohol / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D058185:Magnetite Nanoparticles; D014867:Water; D002244:Carbon; D011142:Polyvinyl Alcohol; D007501:Iron