title: Fe3O4/PANI/P(MAA-co-NVP) multilayer composite microspheres with electric and magnetic features: assembly and characterization.
abstract: A core-shell multilayered composite microsphere with electric and magnetic features was designed and prepared on the basis of mutilayered fabrication. This kind of microspheres was obtained by introducing a rod-like conductive polyanilline (PANI) or its derivatives onto the surface of magnetic Fe3O4 nanoparticles with 4,4'-diphenylmethane diisocyanate as a anchor molecule. Subsequently, the Fe3O4/PANI or Fe3O4/aniline oligomers microspheres, as a secondary core, were covered with a cross-linked shell layer which was constructed by a dispersion polymerization process of methacrylic acid and vinyl pyrrolidone. The structure and morphologies were characterized by using a FTIR, XRD, UV-vis, SEM, TEM and TGA. The average diameter of Fe3O4 nanoparticles prepared is about 10.7 nm, and the PANI nanobars hold the size in the range of about 20.4-25.6 nm. The PANI nanobars are covalently assembled on the surface of Fe3O4 nanoparticles mainly in a mode of extended or horizontal arrangements through XRD and TEM results. The electromagnetic properties were examined based on different polymerization degrees and component ratios of PANI or its derivatives, showing characteristics of soft magnetic materials and controllable conductivity. The multilayer microspheres can be readily used to perform separation and magnetism guide, even electric and pH-modulated drug release in the light of swelling determination and a laser diffraction particle size analyzer, and are potentially of interest for drug targeting purpose.
authors.affiliation: Key Laboratory of Macromolecular Science of Shaanxi Province, School of Chemistry and Materials Science, Shaanxi Normal University, Xi'an 710062, People's Republic of China.
authors.forename: Yan-Ling
authors.initials: YL
authors.lastname: Luo
authors.forename: Li-Hua
authors.initials: LH
authors.lastname: Fan
authors.forename: Gai-Ling
authors.initials: GL
authors.lastname: Gao
authors.forename: Ya-Shao
authors.initials: YS
authors.lastname: Chen
authors.forename: Xiao-Hua
authors.initials: XH
authors.lastname: Shao
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D004337:Drug Carriers / Q000737:chemistry*; D004574:Electromagnetic Fields; D005290:Ferric Compounds / Q000737:chemistry* / Q000528:radiation effects; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008863:Microspheres; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D000814:Aniline Compounds; D004337:Drug Carriers; D005290:Ferric Compounds; D046911:Macromolecular Substances; C416807:polyaniline; C000499:ferric oxide