title: Targeted delivery of polyoxometalate nanocomposites.
abstract: Polyoxometalate/carboxymethyl chitosan nanocomposites with an average diameter of 130 nm are synthesized and labeled with fluorescein isothiocyanate (FITC) for a combined drug-carrier and cellular-monitoring approach. [Eu(β(2) -SiW(11) O(39) )(2) ](13-) /CMC nanospheres as a representative example do not display cytotoxicity for POM concentrations up to 2 mg mL(-1) . Cellular uptake of fluoresecently labelled {EuSiW(11) O(39) }/FITC-CMC nanoparticles is monitored with confocal laser scanning microscopy. Nanoparticle uptake occurs after incubation times of around 1 h and no cyctotoxic effects are observed upon prolonged treatment. The preferential location of the POM/CMC nanocomposites in the perinuclear region is furthermore verified with transmission electron microscopy investigations on unlabeled nanoparticles. Therefore, this approach is a promising dual strategy for the safe cellular transfer and monitoring of bioactive POMs.
authors.affiliation: Institute of Inorganic Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
authors.forename: Georg
authors.initials: G
authors.lastname: Geisberger
authors.forename: Susann
authors.initials: S
authors.lastname: Paulus
authors.forename: Emina Besic
authors.initials: EB
authors.lastname: Gyenge
authors.forename: Caroline
authors.initials: C
authors.lastname: Maake
authors.forename: Greta R
authors.initials: GR
authors.lastname: Patzke
mesh_terms: D016923:Cell Death / Q000187:drug effects; D048271:Chitosan / Q000031:analogs & derivatives / Q000737:chemistry; D016503:Drug Delivery Systems / Q000379:methods*; D006367:HeLa Cells; D006801:Humans; D018613:Microscopy, Confocal; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D017550:Spectroscopy, Fourier Transform Infrared; D017973:Tungsten Compounds / Q000494:pharmacology*; D000099294:Polyoxometalates
chemical_list: D048271:Chitosan; D017973:Tungsten Compounds; C514968:carboxymethyl-chitosan; C102296:polyoxometalate I; D000099294:Polyoxometalates