Flüssigkeitschromatographie-Tandem-Massenspektrometer
Zusammenfassung der Projektergebnisse
The main aim of the purchase of liquid-chromatograph coupled with triple quadrupole mass spectrometer (called later on LC-MS/MS) was to measure various low-molecular organic contaminants of anthropogenic origin, such as pharmaceuticals, pesticides, industrial chemicals, in aqueous matrices. Since these compounds are mainly detected in the concentration range from ng/L to µg/L, they are generally called micropollutants. By quantification of these substances using LC-MS/MS in environmental samples, such as wastewater and surface water, we are able to assess the level of environment pollution. On the other hand, by measurement of micropollutants’ concentrations during water treatment, biological or photochemical, we can evaluate the efficiency of processes. Few examples of our research activities are presented below. Within the project ‘Beyond pollutant removal - understanding the biochemical mechanism of sulfonamide degradation in wastewater and the role of ipso-substitution (DFG-funding; MA 6267/2-1)’, selection of sulfonamides and their metabolites were quantified in wastewater samples, originated from a group of wastewater treatment plants. Sulfonamides, such as sulfamethoxazole, sulfadiazine, sulfacetamide, are popular antimicrobial agents used in human and veterinary medicine. Using purchased device we quantified the extent of wastewater pollution and identified occurring transformation pathways, with a special attention to ipso-substitution. The results were presented in the detailed form in the project report. LC-MS/MS was also used in the project ‘Die bio-elektrochemische Brennstoffzelle als Baustein einer energieerzeugenden Abwasserbehandlungsanlage’ (BioBZ, BMBF-funding: 02WER1317B) that aimed to construct microbial fuel cells (MFC) for production of electric energy and treatment wastewater at the same time. By using LC-MS/MS we demonstrated that in certain conditions, the constructed system is able to remove selected micropollutants, namely, sulfamethoxazole, benzotriazole, 4/5-Methyl-1H-benzotriazole, amidotrizoate, carbamazepine, caffeine, diclofenac from the wastewater, and indeed cause energy production. The BioBZ project gained recognition on the national level, and was honored with Deutscher Nachhaltigspreis 2018. The results of the project have been presented in a project report, and became a basis for the following project Demo-BioBZ (BMBF-funding), which begins in November 2019. The problem of presence of antibiotics (ABs) in surface water was addressed in two PhD projects. In one of these projects, the LC-MS/MS was used to assess the antibiotic pollution of one of the local rivers. Increased ABs concentrations downstream compared to upstream river from the discharge point of the municipal wastewater treatment plant (WWTP) in Karlsruhe, suggested limited efficiency of applied treatment and indicated the WWTP as a source of ABs in natural environment. Later on, the detected concentrations were related to the abundance of antibiotic resistance genes (ARGs) and facultative pathogenic bacteria (FPB). However, very low concentrations of ABs in river waters (low ng/L range), raised doubts if the increase of ARGs and FPB in the downstream river can be justified by ABs input in aquatic environment (Brown et al., 2019, section 2.5). In another PhD project, the photolytic degradation of two groups of ABs was investigated, namely penicillins and oxazolidinones. By using LC-MS/MS we described the kinetics of photodegradation and semi-quantified the proposed transformation products formed during sunlight exposure. We showed that some of the ABs, such as penicillins, are susceptible to degrade by sunlight and a list of transformation products was proposed. On the other hand, oxazolidones, called also antibiotics of last resorts, were more photostable. The results, discussed in two manuscript (one published – Timm et al., 2019, one under review) contributed in the general understanding of the naturally occurring processes in aquatic environment. Overall, the instrument was applied in two third-party-funded projects, two completed (to date) and one on-going PhD projects, three Master projects, one Bachelor project and two study projects. It allowed us to establish the collaboration with thirteen external partners. The collaboration with Dr. hab. Marta Gmurek initiated with short-term research stay founded by German Academic Exchange Service (DAAD) resulted with joint proposal within Humboldt Research Fellowship Programme for Postdoctoral Researchers, which was accepted in July 2019. The findings of the research were collected in the form of two reports, one application note and seven manuscripts (three published, three submitted, one in preparation). By the purchase of LC-MS/MS instrument, we increased our analytical competences and contributed significantly in the field of water research.
Projektbezogene Publikationen (Auswahl)
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Analysis of four β-Lactam antibiotics in water using an Agilent 1290 Infinity II LC and an Agilent 6470 Triple Quadrupole LC / MS with direct injection and online SPE, Application Note.
Timm A., Peschke R. & Horn H.
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Impact of the particulate matter from wastewater discharge on the abundance of antibiotic resistance genes and facultative pathogenic bacteria in downstream river sediments. Science of The Total Environment, 649, 1171-1178.
Brown, Philip C.; Borowska, Ewa; Schwartz, Thomas & Horn, Harald
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Photolysis of four β‑lactam antibiotics under simulated environmental conditions: Degradation, transformation products and antibacterial activity. Science of The Total Environment, 651, 1605-1612.
Timm, Alexander; Borowska, Ewa; Majewsky, Marius; Merel, Sylvain; Zwiener, Christian; Bräse, Stefan & Horn, Harald
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Solar Photocatalytic Degradation of Sulfamethoxazole by TiO2 Modified with Noble Metals. Catalysts, 9(6), 500.
Borowska, Ewa; Gomes, João F.; Martins, Rui C.; Quinta-Ferreira, Rosa M.; Horn, Harald & Gmurek, Marta
