title: The role of PVP in the bioavailability of Ag from the PVP-stabilized Ag nanoparticle suspension.
abstract: We assessed the bioavailability of Ag from Ag nanoparticles (NPs), stabilized with polyvinylpyrrolidone (PVP), to terrestrial isopods which were exposed to 10, 100 and 1000 μg Ag NPs/g of dry food. Different Ag species were determined in the NP suspension that was fed to isopods: (i) total Ag by atomic absorption spectroscopy, (ii) the sum of Ag-PVP complexes and free Ag+by anodic stripping voltammetry at the bismuth-film electrode, and (iii) free Ag+by ion-selective potentiometry. The amounts of Ag species in the consumed food were compared to the masses of Ag accumulated in the isopod digestive glands. Our results show that all three Ag species (Ag NPs, Ag-PVP complexes and free Ag+) could be the source of bioaccumulated Ag, but to various degrees depending on the exposure concentration and transformations in the digestive system. We provide a proof that (i) Ag NPs dissolve and Ag-PVP complexes dissociate in the isopod digestive tract; (ii) the concentration of free Ag+in the suspension offered to the test organisms is not the only measure of bioavailable Ag. The type of NP stabilizer along with the NP transformations in the digestive system needs to be considered in the creation of new computational models of the nanomaterial fate.
authors: Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000, Ljubljana, Slovenia.
authors: Tea
authors: T
authors: Romih
authors: Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000, Ljubljana, Slovenia. Electronic address: anita.jemec@bf.uni-lj.si.
authors: Anita
authors: A
authors: Jemec
authors: Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000, Ljubljana, Slovenia.
authors: Monika
authors: M
authors: Kos
authors: Analytical Chemistry Laboratory, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia.
authors: Samo B
authors: SB
authors: Hočevar
authors: Department for the Synthesis of Materials, Jožef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia.
authors: Slavko
authors: S
authors: Kralj
authors: Department for the Synthesis of Materials, Jožef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia.
authors: Darko
authors: D
authors: Makovec
authors: Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000, Ljubljana, Slovenia.
authors: Damjana
authors: D
authors: Drobne
mesh_terms: D000818:Animals; D001682:Biological Availability; D041981:Gastrointestinal Tract / Q000378:metabolism; D033321:Isopoda / Q000187:drug effects / Q000378:metabolism*; D053768:Metal Nanoparticles / Q000737:chemistry*; D011205:Povidone / Q000737:chemistry*; D012834:Silver / Q000737:chemistry / Q000493:pharmacokinetics*; D013535:Suspensions
chemical_list: D013535:Suspensions; D012834:Silver; D011205:Povidone
keywords: Ag complexes; Ag ions; Ion-selective electrode; Terrestrial isopod; Voltammetry