Fluorescence Spectroscopy and Parafac Analysis to Quantify Interactions Between Metal Ions and Dissolved Organic Matter in Natural Waters

The dissolved organic matter (DOM) in natural waters is composed of a variety of organic compounds and has a number of ecological and geochemical functions, including metal binding and buffering capacity. Metal ions potentially interact with DOM to form complexes, and this interaction influences the transport, bioavailability and potential toxicity of those metal ions, which can play a significant role in environmental and ecological processes. This project is intended to quantify the interaction between DOM and metal ions, using UV-spectroscopy and fluorescence spectroscopy coupled with PARAFAC (Parallel Factor) analysis. Natural surface water samples will be obtained and filtered. Then they will be titrated with metal ion solutions, and spectroscopically analyzed. By assessing the magnitude and nature of the spectroscopic changes induced by the addition of metal ions, detailed information about the metal-DOM interaction can be obtained. The metal ions we are initially interested in are copper (Cu2+), iron (Fe3+), aluminum (Al3+), zinc (Zn2+), vanadium (V2+) and nickel (Ni2+)