Raman-Microscope

• Subject Area: Agriculture, Forestry and Veterinary Medicine
• Term: Funded in 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 538656740

Microplastics (MP, 1-5000 µm) and nanoplastics (NP, plastic particles <1000 nm) can have harmful effects on the environment and human health. However, to date it is not known exactly how much MP and NP is present in the environment and what properties it possesses. This is due to the fact that the methods which are mostly used today for the analysis of MP (e.g. µFTIR) can only analyze particles > approx. 20 µm. For smaller particles there are very few measured values published so far. Therefore we want to acquire a Raman microscope, because with modern Raman microscopes it is possible to identify particles > approx. 0.5 µm chemically and thus to extend the measuring range substantially. This is especially important because on the one hand the number of particles increases with decreasing particle size, on the other hand smaller plastic particles penetrate more easily into plants and other organisms and can cause stronger toxicological effects. Furthermore, the spatially and spectrally high-resolution analysis of single larger plastic pieces and MP can provide more detailed information about the exact chemical composition or e.g. aging processes in plastic particles. In addition to the analysis of plastic particles, the Raman microscope will also be used to analyze the heavy mineral composition of sediments, allowing conclusions about the origin of the sediments. Heavy mineral analysis is traditionally performed on a transmitted-light microscope, which can lead to erroneous determinations and compromise quantitative determinations, even by experienced personnel. With the help of the Raman microscope, such errors can be largely eliminated. In addition, it also opens up the possibility of extending the analysis to finer particle sizes. Of interest here is the group of siltstones, which rank in sedimentary sequences in proportion clearly ahead of the traditionally studied sandstones and have so far been little studied in terms of heavy minerals, although they have a relatively high heavy mineral content due to the high mineral density with a small diameter.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Raman-Mikroskop
• Instrumentation Group: 1840 Raman-Spektrometer
• Applicant Institution: Technische Universität Darmstadt
• Leader: Professor Dr. Moritz Bigalke