title: Chemical and structural characterization of copper adsorbed on mosses (Bryophyta).
abstract: The adsorption of copper on passive biomonitors (devitalized mosses Hypnum sp., Sphagnum denticulatum, Pseudoscleropodium purum and Brachythecium rutabulum) was studied under different experimental conditions such as a function of pH and Cu concentration in solution. Cu assimilation by living Physcomitrella patents was also investigated. Molecular structure of surface adsorbed and incorporated Cu was studied by X-ray Absorption Spectroscopy (XAS). Devitalized mosses exhibited the universal adsorption pattern of Cu as a function of pH, with a total binding sites number 0.05-0.06 mmolg(dry)(-1) and a maximal adsorption capacity of 0.93-1.25 mmolg(dry)(-1) for these devitalized species. The Extended X-ray Absorption Fine Structure (EXAFS) fit of the first neighbor demonstrated that for all studied mosses there are ∼4.5 O/N atoms around Cu at ∼1.95 Å likely in a pseudo-square geometry. The X-ray Absorption Near Edge Structure (XANES) analysis demonstrated that Cu(II)-cellulose (representing carboxylate groups) and Cu(II)-phosphate are the main moss surface binding moieties, and the percentage of these sites varies as a function of solution pH. P. patens exposed during one month to Cu(2+) yielded ∼20% of Cu(I) in the form of Cu-S(CN) complexes, suggesting metabolically-controlled reduction of adsorbed and assimilated Cu(2+).
authors: GET (Géosciences Environnement Toulouse) UMR 5563CNRS, 14 Avenue Edouard Belin, F-31400 Toulouse, France. Electronic address: aridaneglez@gmail.com.
authors: Aridane G
authors: AG
authors: González
authors: Instituto de Ciencia de Materiales Madrid, CSIC, Cantoblanco, E-28049 Madrid, Spain.
authors: Felix
authors: F
authors: Jimenez-Villacorta
authors: Plant Biotechnology, Faculty of Biology, University of Freiburg, Schaenzlestrasse 1, 79104 Freiburg, Germany; State Museum of Natural History Stuttgart, Rosenstein 1, 70191 Stuttgart, Germany.
authors: Anna K
authors: AK
authors: Beike
authors: Plant Biotechnology, Faculty of Biology, University of Freiburg, Schaenzlestrasse 1, 79104 Freiburg, Germany; BIOSS-Centre for Biological Signalling Studies, 79104 Freiburg, Germany; FRIAS-Freiburg Institute for Advanced Studies, 79104 Freiburg, Germany.
authors: Ralf
authors: R
authors: Reski
authors: Department of Agricultural Sciences, University of Naples Federico II, Via Università 100, 80055 Naples, Italy.
authors: Paola
authors: P
authors: Adamo
authors: GET (Géosciences Environnement Toulouse) UMR 5563CNRS, 14 Avenue Edouard Belin, F-31400 Toulouse, France; BIO-GEO-CLIM Laboratory, Tomsk State University, Tomsk, Russia; Institute of Ecological Problems of the North, Russian Academy of Science, Arkhangelsk, Russia.
authors: Oleg S
authors: OS
authors: Pokrovsky
mesh_terms: D000327:Adsorption; D044002:Bryophyta / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D004784:Environmental Monitoring / Q000379:methods*; D006863:Hydrogen-Ion Concentration
chemical_list: D003300:Copper
keywords: Adsorption; Biomonitoring; Copper; XANES; XAS