Pseudopolarography coupled with logarithmic additions for determination of complexing properties of copper with dissolved natural organic matter

摘要: Complexation of trace metals in natural waters by organic matter and inorganic ligands i.e. their chemical speciation, determines mobility bioavailability. NOM is ubiquitous the environment consists a complex mixture [1]. It known to play important roles fate many contaminants due its complexing properties. A better determination structural functional properties can greatly improve our understanding underlying mechanisms responsible for heavy complexation. Among techniques allowing speciation waters, voltammetry really appropriate because it offers high sensitivity, enough selectivity ability direct measurement with minimal disturbance original sample. Obtained voltammetric data are related physico-chemical characteristics electroactive metal species, information on parameters investigated could be obtained. In this study, pseudopolarographic approach [2, 3]. Pseudopolarogram represents series anodic stripping (ASV) peak current values plotted as function deposition potential. As classical polarography, extracted from pseudopolarograms half-wave potential limiting current. The reduction potentials inert complexes separated free labile shifted towards more negative values. amount these shifts basis type they depend stability constant [4]. Pseudopolarography used here, addition logarithmic additions copper, optimise choice accumulation/deposition where only free/labile reduced which prerequisite procedure capacity (MCC) determination. influence accumulation was investigated, well. Copper were performed mode, wider analytical window, therefore accuracy [5]. further modelled PROSECE (Programme d'Optimisation et de SpEciation Chimique dans l'Environnement), very manageable software based discrete model Calculated (ligand concentrations constants) strongly well experimental setup, needs understood quantified.