TY - JOUR A1 - Paul, Andrea ED - Reese, M. ED - Goldhammer, T. ED - Schmalsch, C. ED - Weber, J. ED - Bannick, C. G. T1 - Spectroscopic evidence for adsorption of natural organic matter on microplastics JF - Applied Research N2 - The interaction of microcroplastics (MP) with dissolved organic matter, especially humic substances, is of great importance in understanding the behavior of microplastics in aquatic ecosystems. Surface modification by humic substances plays an essential role in transport and interaction of MP with abiotic and biotic components. Previous studies on the interaction between MP and humic substances were largely based on a model compound, humic acid (Sigma-Aldrich). In our work, we therefore investigated the interaction of natural organic matter (NOM) sampled from a German surface water with low-density polyethylene particles (LDPE). Highpressure size exclusion chromatography (HPSEC) and UV/vis absorption and fluorescence spectroscopy were used to characterize the incubation solutions after modifications due to the presence of LDPE, and Raman spectroscopy was used to characterize the incubated microplastics. While the studies of the solutions generally showed only very small effects, Raman spectroscopic studies allowed clear evidence of the binding of humic fractions to MP. The comparison of the incubation of NOM and a lignite fulvic acid which also was tested further showed that specific signatures of the humic substances used could be detected by Raman spectroscopy. This provides an elegant opportunity to conduct broader studies on this issue in the future. KW - Humic matter KW - Raman KW - HPSEC KW - Fluorescence KW - MCR PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-574519 DO - https://doi.org/10.1002/appl.202200126 SN - 2702-4288 SP - 1 EP - 30 PB - Wiley-VCH CY - Weinheim AN - OPUS4-57451 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hudson, A.D. A1 - Jamieson, O. A1 - Crapnell, R.D. A1 - Rurack, Knut A1 - Soares, T.C.C. A1 - Mecozzi, F. A1 - Laude, A. A1 - Gruber, J. A1 - Novakovic, K. A1 - Peeters, M. T1 - Dual detection of nafcillin using a molecularly imprinted polymer-based platform coupled to thermal and fluorescence read-out JF - Materials Advances N2 - Reported here is the production of molecularly imprinted polymer (MIP) films, integrating a fluorescent moiety that serves as both an element for template interaction and signalling, for the thermal and optical detection of the beta-lactam antibiotic nafcillin. Fluorescein methacrylate (FluMa) was synthesized and introduced during the molecular imprinting process as the sole monomer and in a 1 : 1 mixture with methacrylic acid (MAA), allowing to draw first conclusions on the MIP formation potential of such a rather large and rigid monomer. At first, MIP microparticles containing FluMa were prepared by free radical polymerisation. Optical batch rebinding experiments revealed that FluMa can act as a functional monomer for selective detection of nafcillin; however, the addition of MAA as co-monomer significantly improved performance. Subsequently, thin MIP films containing FluMa were deposited onto functionalised glass slides and the influence of porogen, drying time, and monomer composition was studied. These MIP-functionalised glass electrodes were mounted into a customised 3D-printed flow cell, where changes in the liquid were either evaluated with a thermal device or using fluorescence bright field microscopy. Thermal analysis demonstrated that multiple MIP layers enhanced sensor specificity, with detection in the environmentally relevant range. The fluorescence bright field microscope investigations validated these results, showing an increase in the fluorescence intensity upon exposure of the MIP-functionalised glass slides to nafcillin solutions. These are promising results for developing a portable sensor device that can be deployed for antibiotics outside of a dedicated laboratory environment, especially if sensor design and fluorophore architecture are optimised. KW - Molecularly Imprinted Polymers KW - Fluorescence KW - Antibiotics KW - Heat-transfer Measurements KW - Thin films PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-540044 DO - https://doi.org/10.1039/D1MA00192B VL - 2 IS - 15 SP - 5105 EP - 5115 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-54004 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -