title: Synthesis, characterisation and cytotoxicity of polyoxometalate/carboxymethyl chitosan nanocomposites.
abstract: Chitosan and its derivates continue to attract considerable research interest as effective drug carriers with good biocompatibility and high cellular uptake rates. We used these versatile features to tap the considerable biomedical potential of polyoxometalates (POMs) through their encapsulation into a carboxymethyl chitosan (CMC) matrix. The nanocapsules were prepared by ionic gelification with Ca(2+); their size distribution ranges from 60 to 150 nm. Because [Co(4)(H(2)O)(2)(PW(9)O(34))(2)](10-) is well known for its manifold properties, such as antiviral activity, it was selected as a model POM. The resulting composites were characterised with a wide range of analytical methods, which pointed to quantitative encapsulation of intact POMs within the CMC matrix. We studied the biocompatibility of the POM/CMC nanocomposites on HeLa cells through MTT and proliferation assays. Even after prolonged incubation times at high concentrations, the composites did not display cytotoxicity, thereby drastically reducing the side effects of the pristine POMs. This opens up new avenues for designing novel inorganic drug prototypes from bioactive POMs.
authors.affiliation: Institute of Inorganic Chemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
authors.forename: Georg
authors.initials: G
authors.lastname: Geisberger
authors.forename: Susann
authors.initials: S
authors.lastname: Paulus
authors.forename: Mauro
authors.initials: M
authors.lastname: Carraro
authors.forename: Marcella
authors.initials: M
authors.lastname: Bonchio
authors.forename: Greta R
authors.initials: GR
authors.lastname: Patzke
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D048271:Chitosan / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004337:Drug Carriers; D004354:Drug Screening Assays, Antitumor; D006367:HeLa Cells; D006801:Humans; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D056951:Photoelectron Spectroscopy; D017973:Tungsten Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D000099294:Polyoxometalates
chemical_list: D000970:Antineoplastic Agents; D048271:Chitosan; D004337:Drug Carriers; D017973:Tungsten Compounds; C514968:carboxymethyl-chitosan; C102296:polyoxometalate I; D000099294:Polyoxometalates