title: Cobalt oxide nanoparticles can enter inside the cells by crossing plasma membranes.
abstract: The ability of nanoparticles (NPs) to be promptly uptaken by the cells makes them both dangerous and useful to human health. It was recently postulated that some NPs might cross the plasma membrane also by a non-endocytotic pathway gaining access to the cytoplasm. To this aim, after having filled mature Xenopus oocytes with Calcein, whose fluorescence is strongly quenched by divalent metal ions, we have exposed them to different cobalt NPs quantifying quenching as evidence of the increase of the concentration of Co(2+) released by the NPs that entered into the cytoplasm. We demonstrated that cobalt oxide NPs, but not cobalt nor cobalt oxide NPs that were surrounded by a protein corona, can indeed cross plasma membranes.
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria; Via Dunant 3, Varese, Italy.|Interuniversity Center "The Protein Factory", Politecnico di Milano and Università dell'Insubria, Via Mancinelli 7, I-20131 Milan, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Bossi
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria; Via Dunant 3, Varese, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Zanella
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria; Via Dunant 3, Varese, Italy.|Interuniversity Center "The Protein Factory", Politecnico di Milano and Università dell'Insubria, Via Mancinelli 7, I-20131 Milan, Italy.
authors.forename: Rosalba
authors.initials: R
authors.lastname: Gornati
authors.affiliation: Department of Biotechnology and Life Sciences, University of Insubria; Via Dunant 3, Varese, Italy.|Interuniversity Center "The Protein Factory", Politecnico di Milano and Università dell'Insubria, Via Mancinelli 7, I-20131 Milan, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Bernardini
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism*; D002463:Cell Membrane Permeability; D003035:Cobalt; D003593:Cytoplasm / Q000378:metabolism; D005452:Fluoresceins / Q000378:metabolism; D007477:Ions / Q000378:metabolism; D053768:Metal Nanoparticles; D009865:Oocytes / Q000378:metabolism; D010087:Oxides; D000066970:Protein Corona / Q000378:metabolism; D014981:Xenopus
chemical_list: D005452:Fluoresceins; D007477:Ions; D010087:Oxides; D000066970:Protein Corona; D003035:Cobalt; C060728:cobalt oxide; C007740:fluorexon