Measurement Of Soluble Cuprum In Water By Diffusive Gradient In Thin Film Technique

The biological availability and toxicity of trace metals in aquatic systems is strongly dependent on the metal species present. Trace metals exist in a variety of inorganic and organic forms in aquatic systems, ranging from simple hydrated molecules to large organic complexes, even some suspenders or colloids. So researching the metal species and the relationship between biological absorption and concentration of free metal and according to the chemical form of assessment of the environmental analysis of trace metals is very important, which can supply thermodynamics and dynamics references to develop a relatively simple and easy chemical analytical method instead of biologic analytical method.There are a lot of ways to distinguish trace metal species and predict toxicity of trace metals, Diffusive gradients in thin films technique (DGT) is an in-situ method for the measurement of labile metals. In this paper, the Cu (II) species were measured by home-made DGT devices with the CMC, PSS and PAAS solutions which have different binding strength with cuprum as the binding phases and cellulose dialysis membrane (CDM) as the diffusive phase.The conditional deployment coefficients of cuprum in the CDM were measured with the CMC, PSS and PAAS as the binding phases in the synthetic solution. The conditional stability constants of CMC, PSS and PAAS with Cu (II) were also measured and the effect factors of pH, temperature, ionic strength and stir power were discussed. The selective analysis was analyzed further. The soluble cuprum species were accumulated and measured in the different ratio of EDTA and FA and Cu (II) by DGT devices with CMC, PSS and PAAS as binding phases.From the experiments, we can draw the conclusion that CDM-CMC-DGT, CDM-PSS-DGT and CDM-PAAS-DGT can be used for the measurement of cuprum in water and the mass of cuprum by different binding phases can be significantly different, which suggests that the DGT labile cuprum fractions were dependent on the binding strength of the binding phase. The concentration of Cu (â…¡) species varies from the kinds of binding phases, so it would be possible to use the chemical analytical method instead of the biologic analytical method.