Spatially resolved isotope ratios and element concentrations in biofilms as screening tool for micribiologically influenced corrosion - online coupling of laser ablation with MC-ICP-MS, HR-ICP-MS and ToF-ICP-MS (ISOScreen)

• Applicant: Dr. Jochen Vogl
• Subject Area: Analytical Chemistry
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 470042365

Isotope ratios provide valuable information on the origin and distribution of elements and on reaction processes and their timeline. To obtain detailed information on these chemical processes, especially at interfaces, techniques enabling spatially resolved measurements are required. Such a system will be realized by coupling laser ablation with three inductively coupled plasma mass spectrometers (ICP-MS) – namely a multi-collector ICP-MS, a high-resolution ICP-MS and a time-of-flight ICP-MS – via an aerosol splitter. This will allow for the first time simultaneous and spatially resolved measurements of several isotope ratios and multi-element concentrations. The in-situ obtained sample composition enables online corrections of matrix effects by applying machine learning algorithms. After its validation the developed measurement system will be used to study microbiologically influenced corrosion (MIC) of iron and steel. The focus is here on whether MIC causing microorganisms lead to individual isotope fractionation patterns of iron which differ from those of classical chemical corrosion. In case of significantly large differences in the isotope fractionation patterns the individual corrosion processes can be distinguished based on the iron isotope ratios. With the analysis of real-world samples valuable information on the damage mechanism and the involved microorganisms can be obtained, which in the long term contributes to a fast damage analysis the development of resistant materials.

• DFG Programme: Research Grants