HR: 0830h
AN: B51C-0974    [PDF]
TI: Formation of Kinetically Inert Copper Compounds in the Presence of Sulfide and Thiols
AU: * Blom, L B
EM: lenabb@mit.edu
AF: Massachusetts Institute of Technology, 77 Massachusetts Avenue Room 48-419, Cambridge, MA 02139
AU: Fitzmaurice, A G
EM: agfitz@mit.edu
AF: Massachusetts Institute of Technology, 77 Massachusetts Avenue Room 48-419, Cambridge, MA 02139
AU: Voelker, B M
EM: voelker@mit.edu
AF: Massachusetts Institute of Technology, 77 Massachusetts Avenue Room 48-419, Cambridge, MA 02139
AB: Most of the copper in aquatic environments is bound in compounds that determine the bioavailability and toxicity of the copper but remain unidentified. A recent study has shown that a large fraction of the copper in coastal waters is present in compounds that are kinetically inert to ligand exchange with the strong ligand salicylaldoxime (SA) (Kogut and Voelker, 2003). The goal of this study is to determine whether inert copper compounds are formed in seawater in the presence of sulfide and thiols. Laboratory experiments with water from the Sargasso sea with low levels of NOM was used for experiments where copper, sulfide and cysteine were added and allowed to react. Two analytical techniques for determining concentrations of kinetically inert copper compounds were compared: spectrophotometric detection of copper (I)-bathocuproine after reduction of Cu(II) and pre-concentration of the Cu(I)-bathocuproine complex on a C18 -column, and the previously used competing ligand exchange technique using voltammetric detection of copper-salicylaldoxime complexes.
DE: 4807 Chemical speciation and complexation
SC: Biogeosciences [B]
MN: 2003 Fall Meeting