Development of analytical methods for speciation analysis of copper and zinc-based antifouling agents in surface water

接触水环境(如S船体、水利工程中的建筑)的表面会受到污垢物质的结垢，即所谓的生物污垢。在水利工程中，生物污垢会对船体造成较大的损伤，如船体水摩擦增大、干扰建筑物的使用能力等。因此，今天正在使用以铜和锌络合物为基础的防污杀菌剂(例如，吡硫酮)。由于缺少用于直接检测和形态分析的适当分析工具，这些金属络合物的环境行为尚未完全揭开。此外，还可能与更多的二价金属阳离子发生转金属作用，从而影响水环境中金属离子的生物有效性和迁移性。因此，本项目的主要目标是：i)开发合适的辅助分析方法，用于金属基防污杀菌剂的形态分析。鉴于离子物质或至少是极性物质正在研究中，方法的开发是基于毛细管电泳联用高分辨率分子和互补元素质谱仪(CE/ESI-Q-ToF-MS&lt；=&gt；CE/ICP-SFMS)。CE/ESI-Q-ToF-MS可以根据准确的分子质量以及MS/MS实验和特征裂解模式进行明确的物种鉴定。然而，ESI-MS表现出物种特异性的检测器响应。因此，将在物种独立响应的基础上，采用互补的CE/ICP-SFMS耦合来进行物种量化。此外，同位素比率的测定使浓缩的稳定同位素(如65Cu、67Zn)能够用于追踪和定量目的。ii)在开发方法时，将进行实验室规模的浸出实验，并在实验过程中增加基质的复杂性。在这些实验的基础上，将阐明金属基防污杀菌剂的形态和转金属行为。由于在实验室试验中获得的经验，将确定有选择和不变的目标物种(作为以前原始金属络合物的指示物)。iii)根据所确定的目标物种，将对从码头/港口采集的真实地表水样本进行分析，以评估防污生物剂对水环境的投入和环境污染。最后，开发的方法将得到简化，以便广泛适用并转移到其他实验室。完全放弃防污染物质(目前)是不可能的，因为环境合理的替代方法目前还不够强大。因此，需要使用分析方法来更有针对性和更有效地使用防污物质。

Surfaces in contact with the aquatic environment (e.g., ship´s fuselage, constructions in hydraulic engineering) are subjected to incrustation of fouling matter, so called bio-fouling. Bio-fouling leads to strong impairment with regard to, e.g., increase of ship´s water-friction, interference of operational capability of constructions in hydraulic engineering. Thus, today anti-fouling biocides on the basis of copper- and zinc-complexes are being used (e.g., pyrithiones). The environmental behavior of these metal-complexes is not fully unraveled yet, due to the fact that appropriate analytical tools for direct detection and speciation analysis are missing. Furthermore, transmetalation with further bivalent metal-cations is likely, thus influence the bioavailability and mobility of metal ions in the aquatic environment. However, investigations on this aspect are missing.Consequently, the main objectives of this project are:I) The development of appropriate complementary analytical methods for speciation analysis of metal-based anti-fouling biocides. Given the fact that ionic or at least polar substances are under investigation, method development is based on on-line coupling of capillary electrophoresis (CE) with high resolution molecular- as well as complementary elemental-mass spectrometry (CE/ESI-Q-ToF-MS <=> CE/ICP-SFMS). CE/ESI-Q-ToF-MS allows for an unambiguous species-identification on basis of exact molecular masses as well as MS/MS experiments and characteristic fragmentation pattern. Though, ESI-MS exhibits a species-specific detector response. Therefore, complementary CE/ICP-SFMS coupling will be deployed for species quantification on basis of a species-independent response. Furthermore, the determination of isotope ratios enables the application of enriched stabile isotopes (e.g., 65Cu, 67Zn) for tracing and quantification purposes.II) Upon method development lab-scale leaching-experiments will be conducted and complexity of the matrix will be increased during the course of experiments. On basis of these experiments the speciation and transmetalation behavior of metal-based anti-fouling biocides will be elucidated. Owing to the experience gained during the lab-scale experiments selective and invariant target species will be identified (acting as indicators of the formerly pristine metal-complexes).III) Based on the target species identified, analysis of real surface water samples collected from marinas/harbors will be conducted to assess the input as well as environmental pollution of antifouling biocides into the aquatic environment. Finally, the developed methods will be simplified to be widely applicable and transferable to other laboratories.Complete abandonment of anti-fouling substances is (currently) impossible, as environmentally justifiable alternative approaches are at present not robust enough. Thus, analytical methods are needed to end up with a more targeted and efficient use of anti-fouling substances.