A general challenge in the detection and quantification of pathogens and antibiotic resistant bacteria are low quantities in water and the acceptance for regulatory issues. While cultivation methods remain the gold standard for microbial detection, their inherent limitations—such as prolonged incubation times and restriction to cultivable organisms—necessitate the exploration and validation of cultivation-independent, rapid bioanalytical techniques.

These rapid methods have demonstrated robust applicability across diverse environmental matrices, including groundwater, drinking water, surface water, and seawater if concentration methods (e.g. crossflow ultrafiltration, immunomagnetic magnetic, adsorption / elution methods) are combined with detection methods (e.g. Flow cytometry, (d)qPCR, biosensors). The critical next step involves systematic comparison and validation of these methods to ensure their reliability and reproducibility. Therefore, we work together with experts group “Pathogens and Antibiotic resistant bacteria” at the GDCh Society of Water Chemistry Division.

For effective translation from research to practical application, it is imperative that analytical instruments and reagents for microbiology are optimized for end-users within water chemistry contexts, enabling stringent quality assurance. This necessitates comprehensive standardization encompassing the entire analytical workflow: from sample collection and preparation to analysis, data evaluation, statistical treatment, and final assessment.

Key publications

Göpfert, L.; Klüpfel, J.; Heinritz, C.; Elsner, M.; Seidel, M. Macroporous epoxy-based monoliths for rapid quantification of Pseudomonas aeruginosa by adsorption elution method optimized for qPCR. Analytical and Bioanalytical Chemistry, 2020, 412, 8185–8195. 
https://doi.org/10.1007/s00216-020-02956-3. 

Kunze, A.; Dilcher, M.; Abd El Wahed, A.; Hufert, F.; Niessner, R. and Seidel, M., On-Chip Isothermal Nucleic Acid Amplification on Flow-Based Chemiluminescence Microarray Analysis Platform for the Detection of Viruses and Bacteria. Analytical Chemistry, 2016, 88, 898–905. DOI:10.1021/acs.analchem.5b03540.

Streich, P.; Redwitz, J.; Walser-Reichenbach, S.; Herr, C.E.W.; Elsner, M.; Seidel, M. Culture-independent quantification of Legionella pneumophila in evaporative cooling systems using immunomagnetic separation coupled with flow cytometry. Applied Microbiology 2024, 4, 284-296. DOI: 10.3390/applmicrobiol4010019. 

Wunderlich, A.; Torggler, C.; Elsaesser, D.; Lück, C.; Niessner, R.; Seidel, M., Rapid quantification method for Legionella pneumophila in surface water. Analytical and Bioanalytical Chemistry, 2016, 408(9), 2203-2213. DOI: 10.1007/s00216-016-9362-x.