TY - CONF A1 - Gojani, Ardian T1 - Combined Raman and LIBS using Spatial Heterodyne Spectrometer with High Repetition Rate Laser N2 - Spatial heterodyne spectroscopy is used for Raman and laser-induced breakdown spectroscopy of six rocks with various mineral content, using high repetition rate diode-pumped solid state lasers. While LIBS data are obtained for all samples, Raman signal was determined only for half of those. This work shows that it is possible to combine LIBS and Raman spectrometry into a single instrument consisting of a DPSS laser for excitation and SHS for spectral recording. For better results and gain from complementary spectrochemical information that the system provides, it is necessary to optimize light collection. T2 - 2020 Winter Conference on Plasma Spectrochemistry CY - Tucson, Arizona, USA DA - 13.01.2020 KW - Laser-Induced Background Spectroscopy KW - Spatial heterodyne spectroscopy KW - Raman spectroscopy PY - 2020 AN - OPUS4-50265 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pignatelli, Giuseppe T1 - Optical Sensor for Monitoring Quality of 3D Metal Printing N2 - Additive Manufacturing (AM) becomes widespread in many technological fields including the precise machining of steel. To assure quality of final products, thorough monitoring of online process is required. We test several monitoring techniques during the AM printing to quickly detect and possibly correct flaws while building a workpiece. Here we show how optical emission spectroscopy can be used to recognize defects that are artificially introduced on a steel printing substrate. T2 - Scix 2020 CY - Online meeting DA - 12.10.2020 KW - Additive manufacturing KW - Spectroscopy KW - Analytical chemistry PY - 2020 AN - OPUS4-51858 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ecke, Alexander T1 - An Immunosensor for Pharmaceutical Contaminants in Water Supply N2 - Contamination of drinking water with pharmaceuticals is an emerging problem and a potential health threat. Immunochemical methods based on the binding of the analyte to specific antibodies enable fast & cost-effective on-site analyses. Magnetic bead-based immunoassays (MBBAs) allow for implementation into an immunosensor for online testing. Particles are prepared by either coupling the analyte molecule (diclofenac) or the respective antibody (amoxicillin) to the surface. For miniaturization, detection is performed electrochemically (chronoamperometry) on a microfluidic chip. The developed immunosensor will enable detection of pharmaceuticals directly in water supply pipes. T2 - Analytica Conference CY - München, Germany DA - 21.06.2022 KW - Immunosensor KW - Magnetic Particles KW - Microfluidics KW - Amperometry KW - Diclofenac KW - Amoxicillin PY - 2022 AN - OPUS4-55381 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pignatelli, Giuseppe T1 - Optical emission spectroscopy as monitoring tool for ded N2 - This presentstion explains how optical emission spectroscopy can be exploited to on line monitor a DED printing production. This technique is tested printing on a substrate with artificial defects. T2 - 1st Workshop on In-situ Monitoring and Microstructure Development in Additive Manufacturing CY - Online meeting DA - 10.12.2020 KW - Monitoring KW - Spectroscopy KW - Analytical chemistry KW - Additive manufacturing PY - 2020 AN - OPUS4-51877 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Prakash, Swayam T1 - Silane Functionalized Paper Test Strips for Rapid and Sensitive Faecal Pigments Detection towards On-site Water Quality Testing N2 - Introduction. W.H.O estimated that globally at least 2 billion people use drinking water sources contaminated with faeces and according to UNICEF, most of these faecal detection methods are expensive, time-consuming (18–24 h time to result), and, with few exceptions, not suited for on-site analysis. Hence, there is an urgent need for the development of analytical methods that allow to unequivocally test for drinking water quality directly on-site. Aims. Development of rapid and sensitive fluorescence based analytical methods for faecal pigments (FPs) detection towards on-site water quality testing. Methods. Silane functionalized glass fiber paper test strips were developed for the sensitive drop-&-detect analysis of FPs. Drop casting of water samples containing faecal pigment on specifically functionalized test strips allowed the sensitive detection of FPs with a smartphone coupled to a 3D printed optical setup. Results. A series of silanes were used to functionalize glass fiber paper and tune its hydrophobicity, exploiting the influence of matrix tailoring to enhance binding of the Zn salt used as co-reagent to urobilin for optimal fluorescence response. Combination of bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane with zinc chloride-impregnated test strips demonstrated optimum fluorescence response for sensitive (nano- and sub-nanomolar concentration) smartphone-based faecal pigments detection. The obtained fluorescence sensing results were validated with a benchtop fluorometer. Furthermore, the developed analytical method was successfully applied to the analysis of real water samples. Conclusions. The possibilities of matrix tailoring and co-reagent nature on the development of a rapid, sensitive, and embedded fluorescence-based on-site strip test are presented and discussed. This technique has potential application for faecal biomarker detection/primary screening for water quality in developing countries, where sophisticated instruments may not be available. T2 - 18th Conference of Methods and Applications in Fluorescence CY - Valencia, Spain DA - 08.09.2024 KW - Faecal contamination KW - Fluorescence KW - Metal complexes KW - Water analysis PY - 2024 AN - OPUS4-61479 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mantha, Anant T1 - Immobilised gold nanoparticles for an optofluidic SERS platform N2 - The combination of SERS with microfluidics not only miniaturises the system but also introduces the possibility to control the environmental parameters of the analyte, which is not present when using either a droplet or cuvette. This allows for applications involving tiny sample volumes and control of sample environments. Direct usage of nanoparticles in solution with the analyte can cause the adsorption of the nanoparticles onto the surfaces of microfluidic systems, leading to undesirable memory effects. By using plasmonic nanoparticles of gold, silver or a mixture of the two, immobilised on removable glass or PDMS inserts, the life and reusability of the channels can be largely improved [1] because they can be inserted into the channel and replaced after use. Using immobilised nanoparticles also introduces a relatively large surface that can be scanned and can improve the reproducibility of the nanoparticle substrate properties and hence the measured spectra. Here, we will discuss strategies for the fabrication and characterization of immobilised plasmonic nanoparticles for bioanalytical applications in optofluidic systems. We will present the plasmonic properties as well as surface-enhanced Raman scattering (SERS) data of relevant compounds. T2 - Molecular Plasmonics 2025 CY - Jena, Germany DA - 15.05.2025 KW - SERS KW - Microfluidics KW - Mikrofluidik PY - 2025 AN - OPUS4-63259 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bell, Jérémy A1 - Biyikal, Mustafa A1 - Rurack, Knut T1 - Embedded sensor based on tandem smartphone-microfluidic device for the detection of TNT in surface and sea waters N2 - The globe's seas were used as dumping ground after the world wars and those millions of ammunition, most of all containing 2,4,6-trinitrotoluene (TNT), represent a pressing danger for fishermen, dredging operations, submarine cable installations and tourism. We developed an extremely selective indication method for TNT based on a specific reaction that produces a highly fluorescent compound. The indication system was integrated into a microfluidic PDMS chip for the solid-liquid extraction of TNT from water samples, offering environmental monitoring possibilities. Combining the advantages of a light-up indicator, microfluidics and a smartphone as detector, the embedded sensor allows for the remote and rapid detection of TNT down to ng in surface and sea waters. T2 - µTAS 2020 CY - Online meeting DA - 05.10.2020 KW - Smartphone KW - Rapid test KW - TNT KW - Ammunition KW - Schnelltest KW - Munition PY - 2020 AN - OPUS4-51444 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rurack, Knut T1 - Multifunctional hybrid microparticles for rapid cytometric and microfluidic mix-&-detect bioassays N2 - Besides the application-oriented parameters selectivity and sensitivity, simplicity and speed as well as robustness and reliability are the key features that determine success, dissemination and acceptance of analytical assays and methods for use in the field. For bioassays based on antibodies or nucleic acid binders, bead-based assays have become one of the main working horses of lab-based methods. However, these approaches are often limited by complicated and time-consuming workflows, which are mainly compensated by massive parallelisation, keeping the average cost and time-to-result within acceptable limits due to the sheer number and constant flow of samples processed. In on-site applications, where analyses need to be performed on suspicion or on demand because results are needed as quickly as possible for proactive decision making, the number, frequency and type of samples are much more diverse, so analytical assays need to be adapted to remain cost-effective and operable by non-expert users in environments where no lab infrastructure is available. With this in mind, we have developed a multifunctional hybrid microparticle platform that enables fast and simple mix-&-detect bioassays in combination with fluidic cytometry- and chip-based analytical methods. The present contribution will give an overview of the beads, their functions and how they can be combined with immunoanalytical and nucleic acid-based detection technologies. Starting from simple polymeric core/silica shell particles [1], we have progressively introduced coding [2,3], anti-fouling [2], high-surface area [4] and magnetic schemes [5] and in recent years have shown how these beads can be used in simple mix-&-detect assays for a range of different environmental, health and food analytes [1-5]. In addition to cytometry, we have also successfully implemented such assays using miniaturised microfluidic and strip-based approaches [6]. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - Bead-based assay KW - Core-shell particles KW - Lab-on-a-chip KW - Mycotoxin PY - 2025 AN - OPUS4-62766 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Garrido, E. T1 - Dualplex lateral flow assay for simultaneous scopolamine and cannibal drug detection based on receptor-gated mesoporous nanoparticles N2 - Drug facilitated sexual assaults (chemical submission) consists in the criminal administration of psychoactive substances without the permission of the victim. Among these compounds, scopolamine (SCP) (commonly well-known as burundanga} has emerged as the perfect psychotropic substance for aggressors because its ingestion induces automatism in the brain of the victim causing a state of submission. Physiologically, an appealing feature of SCP is their relevant role as a non-competitive muscarinic acetylcholine receptor antagonist with rapid and robust antidepressant effects in humans and other species. Specifically, SCP is able to block or dampen the biological response because of binding to an allosteric recombinant human muscarinic acetylcholine receptor M2/CM2 (Mi-AChR) site that is separate from the active recognition site of acetylcholine, thereby inhibiting the effects of the natural substrate and even of a potent agonist such as bethanechol. Here, a straightforward portable strip in combination with bioinspired hybrid nanomaterials for SCP drug in situ and at site detection was developed. The strips allow direct identification of SCP in diluted saliva down to 40 nM in less than 15 min using a smartphone for readout. For this purpose, we prepared a nanosensor based on mesoporous silica nanoparticles {MSNs) loaded with a fluorescent dye and functionalized with bethanechol. Attachment of the M2-AChR 'cap' to the silica scaffold enabled pore closure through non-covalent recognition. interactions with the anchored bethanechol moieties. In the presence of SCP pores were opened, due to the preferential interaction of the drug with receptor, thus releasing the encapsulated reporter and allowing it to be detected. Additionally, to a single-track strip, the extraordinary modularity of the hybrid biosensor materials in combination with the strip-pattering technologies enabled us to obtain a dual-channel strip for SCP and cannibal drug detection in a simple way, providing comparable analytical performance, while enabling further tailoring to the user's needs. T2 - XVI International Workshop on Sensors and Molecular Recognition CY - Valencia, Spain DA - 06.07.2023 KW - Schnelltest KW - Vor-Ort-Analytik KW - Drogen KW - Indikatorfreisetzung KW - Lateral Flow Assay PY - 2023 AN - OPUS4-57943 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tobias, Charlie T1 - Design and Application of Polymer-core/ Silica-shell Particles as Promising Tools for Multiplexed Assays N2 - The simultaneous detection of different analytes has gained increasing importance in recent years, especially in the fields of medical diagnostics and environmental analysis. Multiplex assays allow for a range of biomarkers or pollutants to be rapidly and simultaneously measured. Particularly suitable formats for multiplexing are bead-based assays. The beads employed need to fulfil size and density requirements, important for instance for flow cytometry, and shall exhibit a high modularity to be facilely adapted to various kinds of analytes and detection systems. Core/shell particles are ideally suited in this sense because of their modularity in design and adaptability for various (bio)analytical assays. Here, polystyrene particles coated with different kinds of shells are presented, possessing features that are useful for a multitude of assay formats. The particles in focus were coated with mesoporous and non-porous silica shells, with the possibility to introduce magnetic features to facilitate easier handling dependent on the assay format (e.g., in microfluidics). With high throughput analyses in mind, cytometric model assays were developed. Different factors such as pH or mediator salt used during shell preparation were evaluated with shell inspection by electron microscopy (SEM/TEM/EDX) being key to architectural control of the monodisperse particles. The optimized core/shell particles can be functionalized with capture biomolecules for toxins, viruses, or drugs to demonstrate particle performance. Showing how tailoring of the shell’s surface area controls sensitivity and dynamic range of the assay, an antibody-based assay for the detection of mycotoxins and a multiplex assay for the determination of DNA from different human papilloma virus (HPV) lines were developed. T2 - ICASS 2022 CY - Palma, Mallorca, Spain DA - 25.04.2022 KW - Core–shell particles KW - Multiplexing KW - Surface area control KW - Cytometry PY - 2022 AN - OPUS4-54752 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -