Significance of data treatment and experimental setup on the determination of copper complexing parameters by anodic stripping voltammetry

摘要: Different procedures of voltammetric peak intensities determination, as well various experimental setups were systematically tested on simulated and real data in order to identify critical points the determination copper complexation parameters (ligand concentration conditional stability constant) by anodic stripping voltammetry (ASV). Varieties titration sets (Cu(measured)vs. Cu(total)) fitted models encompassing discrete sites distribution one-class two-class binding ligands (by PROSECE software). Examination different for applied voltammograms with known preset values revealed that tangent fit (TF) routine should be avoided, both it produced an additional class strong ligand (actually not present). Peak fitting whole voltammogram was found most appropriate, provided reliable parameters. Tests performed seawater samples under conditions addition importance proper accumulation time (control sensitivity) equilibration needed complete added during kinetics) are keypoints obtain results free artefacts. The consequence overestimation underestimation complexing is supported illustrated example concentrations (the bioavailable/toxic specie) calculated all studied cases. Errors up 80% almost two orders magnitude constant registered case ligands.