title: The targeted antibacterial and antifungal properties of magnetic nanocomposite of iron oxide and silver nanoparticles.
abstract: Two types of magnetic binary nanocomposites, Ag@Fe(3)O(4) and γ-Fe(2)O(3)@Ag, were synthesized and characterized and their antibacterial activities were tested. As a magnetic component, Fe(3)O(4) (magnetite) nanoparticles with an average size of about 70 nm and monodisperse γ-Fe(2)O(3) (maghemite) nanoparticles with an average size of 5 nm were used. Nanocomposites were prepared via in situ chemical reduction of silver ions by maltose in the presence of particular magnetic phase and molecules of polyacrylate serving as a spacer among iron oxide and silver nanoparticles. In the case of the Ag@Fe(3)O(4) nanocomposite, silver nanoparticles, caught at the surfaces of Fe(3)O(4) nanocrystals, were around 5 nm in a size. On the contrary, in the case of the γ-Fe(2)O(3)@Ag nanocomposite, ultrafine γ-Fe(2)O(3) nanoparticles surrounded silver nanoparticles ranging in a size between 20 and 40 nm. In addition, the molecules of polyacrylate in this nanocomposite type suppress considerably interparticle magnetic interactions as proved by magnetization measurements. Both synthesized nanocomposites exhibited very significant antibacterial and antifungal activities against ten tested bacterial strains (minimum inhibition concentrations (MIC) from 15.6 mg/L to 125 mg/L) and four candida species (MIC from 1.9 mg/L to 31.3 mg/L). Moreover, acute nanocomposite cytotoxicity against mice embryonal fibroblasts was observed at concentrations of higher than 430 mg/L (Ag@Fe(3)O(4)) and 292 mg/L (γ-Fe(2)O(3)@Ag). With respect to the non-cytotoxic nature of the polyacrylate linker, both kinds of silver nanocomposites are well applicable for a targeted magnetic delivery of silver nanoparticles in medicinal and disinfection applications.
authors.affiliation: Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University, Slechtitelu 11, 78371 Olomouc, Czech Republic. robert.prucek@upol.cz
authors.forename: Robert
authors.initials: R
authors.lastname: Prucek
authors.forename: Jiří
authors.initials: J
authors.lastname: Tuček
authors.forename: Martina
authors.initials: M
authors.lastname: Kilianová
authors.forename: Aleš
authors.initials: A
authors.lastname: Panáček
authors.forename: Libor
authors.initials: L
authors.lastname: Kvítek
authors.forename: Jan
authors.initials: J
authors.lastname: Filip
authors.forename: Milan
authors.initials: M
authors.lastname: Kolář
authors.forename: Kateřina
authors.initials: K
authors.lastname: Tománková
authors.forename: Radek
authors.initials: R
authors.lastname: Zbořil
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology; D000935:Antifungal Agents / Q000737:chemistry* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D005290:Ferric Compounds / Q000737:chemistry* / Q000494:pharmacology; D005658:Fungi / Q000187:drug effects; D008280:Magnetics; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry*; D051379:Mice; D008826:Microbial Sensitivity Tests; D053761:Nanocomposites / Q000737:chemistry*; D010316:Particle Size; D012834:Silver / Q000737:chemistry* / Q000494:pharmacology; D015204:Spectroscopy, Mossbauer
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D005290:Ferric Compounds; C000499:ferric oxide; D012834:Silver