LC-MS/MS system (High-performance liquid chromatograph with triple quadrupole mass spectrometer)

• Subject Area: Agriculture, Forestry and Veterinary Medicine
• Term: Funded in 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 550061094

We have successfully utilized targeted liquid chromatography coupled with triple quadrupole mass spectrometry (LC-MS/MS) for several years to investigate toxins and other substances in various foods. We develop and validate sensitive methods for mass spectrometry and contribute to expanding the scientific database that informs risk assessments. We are currently seeking a replacement for our inherited LC-MS/MS system, which was passed to Professor Guldimann upon her appointment. The desired replacement is a high-performance liquid chromatograph coupled with an exceptionally sensitive triple quadrupole mass spectrometer. This new system will be exclusively used in research, focusing on analyzing the fate of toxins such as (i) pyrrolizidine alkaloids, (ii) tropane alkaloids and (iii) mycotoxins along the food chain, as well as the characterization of (iv) naturally occurring antimicrobial substances. Our primary focus is on the analysis of pyrrolizidine alkaloids and their N-oxides (PA/PANO). These hepatotoxic and carcinogenic secondary plant metabolites can enter the food chain through sources like contaminated feed. Our chair leads a collaborative research initiative that has demonstrated the transfer of PA/PANO from feed to milk in ruminants. If contaminated milk is used for cheese production, a significant portion of these compounds passes into the whey. In a follow-up study, we aim to explore the stability of PA/PANO during the thermal processing of milk and whey products (pasteurized, condensed, and UHT milk, as well as powders). Milk and whey are often preserved through heat treatment and processed into powders that are then utilized in baby food or sports nutrition. The concentration effect during the drying process to powders is of particular concern. Presently, there is insufficient data regarding the fate of PA/PANO during thermal processing, which introduces considerable uncertainty into the risk analysis regarding PA/PANO for these products. In a separate project, we investigate naturally occurring antimicrobials against Listeria monocytogenes. Certain cultivars of carrots exhibit remarkable efficiency in killing this significant foodborne pathogen. We study the mechanisms underlying carrots' action against L. monocytogenes and aim to characterize the active substance using LC-MS/MS. Furthermore, we have established sensitive detection methods for mycotoxins and tropane alkaloids in various foods for our research. A reliable LC-MS/MS system is indispensable for the successful implementation of this research. The current system, constructed in 2005, incurs substantial costs due to technical failures, extended downtimes, and resultant delays in project advancement. The conclusion of our ongoing project in March 2024 presents an ideal moment for transitioning to a new system. This would provide a solid instrumental foundation for future research and ensure that funding for projects is used responsibly and efficiently.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: LC-MS/MS System (Hochleistungsflüssigkeitschromatograph mit Triple-Quadrupol-Massenspektrometer)
• Instrumentation Group: 1700 Massenspektrometer
• Applicant Institution: Ludwig-Maximilians-Universität München
• Leader: Professorin Claudia Guldimann, Ph.D.