Design, development and application of a 3D-printed passive air-water sampler for environmental pollution studies

• Applicants: Amir Salemi, Ph.D.; Professor Dr. Torsten Schmidt
• Subject Area: Analytical Chemistry
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 537712128

Passive sampling is an important strategy for collecting reliable and representative environmental contamination data. However, the conventional method of passive sampling misses the water headspace and the chemicals which are exchanged between water and the adjacent air. Current passive samplers have been successfully utilized for either water or air contaminants analysis. They have been introduced in various sizes, designs, structures and the composition of the sorbing phases. However, as this diversity implies, each one has its advantages and disadvantages. In addition, in the case of the studies in which air-water exchange is the main objective (or a part of that), the physical separation of the water and air samplers and the distance between them leads the two samplers to represent environments that may also be influenced by independent factors. So, the relationship between the presence and the concentrations of the compounds and their relevance to the other phase (water-air) could be missed or misinterpreted. In this proposal, a novel passive sampler will be developed to simultaneously collect samples from surface water and its adjacent headspace. This way, the samplers will represent a realistic water-air exchange environment. Another noteworthy aspect of the presented study will be the application of 3D printing to produce the primary models and the modified version of the samplers. This would lead to a cost-effective and extremely flexible development procedure and easily opens the path for future modifications and advancements of the presented setup. To show the applicability of the idea, the developed sampler would be implemented in the non-target analysis of the organic contaminants in surface water samples of various matrices (such as highly contaminated samples and/or waters of different salinity, etc.). Regarding the wide range of the collected contaminants, both gas and liquid chromatographic instruments will be used throughout the analytical procedure and hence to produce a more holistic picture of the studied water, joint GC/LC data processing for headspace and water samples in the NTS context will be implemented. Furthermore, an on-site water-headspace microextraction methodology will be developed, optimized and validated, for grab samples. The results of this technique, as a complementary method, will be compared with the passive sampling. This approach is the first of its kind and will be based on advanced chemometrics data evaluation methods, as described in the proposal.

• DFG Programme: Research Grants
• Co-Investigators: Professor Michael Giese, Ph.D.; Professorin Maryam Vosough, Ph.D.