Comparison of physicochemical speciation procedures with metal toxicity to Chlorella pyrenoidosa. Copper complexation capacity
✍ Scribed by G. M. P. Morrison; T. M. Florence
- Book ID
- 102829735
- Publisher
- John Wiley and Sons
- Year
- 1989
- Tongue
- English
- Weight
- 537 KB
- Volume
- 1
- Category
- Article
- ISSN
- 1040-0397
No coin nor oath required. For personal study only.
✦ Synopsis
A comparison was made of methods for measuring the copper complexation capacity o f natural and synthetic organic ligands in freshwaters. Complexation capacity values close to theoretical were obtained for nitrilotriacetic acid (NTA) and ethyknediaminetetraacetic acid, when the following separation or analysis methods were used t o detect ionic copper: algal a hydroxide resin, ion-selective electrode (ISE), and anodic film electrode (MFE) and Nafion-coated MFEs. N o complexation capacity could be measured for Cu-NTA when the hanging mercury drop electrode (NMDE) was used.
Results from the ISE and a resin with adsorbed aluminum hydroxide agreed closely with algal for the copper complexation capacity of solutions o f fulvic acid and Fe-humic colloids. Analysis IIY at the HMDE, MFE, and Nafion-coated MFE gave values of more than an order of magnitude lower than the other techniques because these methods failed t o detect the end point for partially labile complexes with a large complexation capacity. On the other hand, the use of differential pulse polarography ( DPP) detected these labile copper complexes and yielded results COmpdrdbk with those for algal assay.
Comparable copper complexation capacities for pristine river water samples were obtained by algal M Cu) and I>PP (2.0-3.7 X lo-" M Cu), with lower values for the aluminum hydroxide resin (0.8-1.1 X X lop6 M Cu), they are clearly unsuitable for the determination o f the complexation capacity o f freshwaters.
(Chlorellu pyrenoidosu), an aluminum ping voltammetry (ASV) at the mercury y (2.5-4.1 X M Cu). Hecause the ASV techniques gave much lower results (0.1-0.4
' To wliom corrcspoiidence should be acldressecl.