TY - RPRT A1 - Rurack, Knut A1 - Resch-Genger, Ute T1 - Design, Synthese und Charakterisierung von Fluoreszenzstandards und Fluoreszenzmarkern für die zeitaufgelöste Fluorometrie N2 - Im Rahmen dieses Projekts wurden Fluoreszenzfarbstoffe und neue intrinsische und konjugierte Fluoreszenzmarker mit Sauerstoff, Schwefel, Stickstoff-Heteromakrozyklen als kationenspezifische Rezeptoren für analytische Applikationen der zeitaufgelösten Fluorometrie von der Kiewer Gruppe synthetisiert. Die in Berlin an diesen Verbindungen durchgeführten fluorometrischen Charakterisierungen und spektroskopischen Untersuchungen zum Kationenkomplexierungsverfahren ermöglichten die Aufstellung von ersten Designprinzipien für Fluoreszenzmarker für Übergangs- und Schwermetallionen. T3 - BAM Forschungsberichtreihe - 223 PY - 1998 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-2273 SN - 978-3-89701-038-0 SN - 0938-5533 VL - 223 SP - 1 EP - 40 PB - Wirtschaftsverlag NW CY - Bremerhaven AN - OPUS4-227 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Resch-Genger, Ute A1 - Rurack, Knut ED - Lieberman, R. T1 - Steady-state and time-resolved fluorometry of fluorescent pollutants and heavy metal complexes N2 - Time-resolved laser-induced fluorescence spectroscopy is one of the most sensitive optical methods which is well suited for on-line in situ analysis. Here, three examples for the steady- state and time-resolved fluorescence analysis of environmentally important analytes, the fluorescent monoaromatic hydrocarbons benzene, toluene, and xylene as well as non fluorescent heavy metal ions forming a fluorescent complex with a cation coordinating fluorescence probe, are presented and the potential of both methods is discussed. For BTX, various mixtures of the spectrally similar compounds B, T, and X showing different fluorescence lifetimes were studied with both methods. As an example for fluorometric metal ion analysis, the fluorescence probe BP(OH)2 (2,2'-bipyridyl- 3,3'-diol) was employed for the determination of d10 metal ions in water and the newly developed fluorescence probe APTA for the detection of Cu(II). Cation complexation of BP(OH2 yields spectrally very similar complexes which differ in their fluorescence lifetimes. Complexation of APTA to Cu(II) leads to small spectral changes and a strong increase in fluorescence quantum yield and lifetime. For the analytes studied, a comparison of the detection limits, standard deviations, and linear dynamic range of both methods clearly demonstrates the analytical potential of time-resolved fluorometry. T2 - Conference CY - Munich, Germany DA - 1997-06-16 KW - Fluorescence KW - Time-resolved KW - Probe KW - Heavy metal ion KW - Cation complex PY - 1997 SN - 0-8194-2526-5 DO - https://doi.org/10.1117/12.276139 SN - 1605-7422 N1 - Serientitel: SPIE proceedings series – Series title: SPIE proceedings series IS - 3105 SP - 96 EP - 103 PB - SPIE CY - Bellingham, Wash. AN - OPUS4-2099 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Unger, Brita A1 - Rurack, Knut A1 - Müller, Ralf A1 - Jancke, Harald A1 - Resch-Genger, Ute T1 - Microscopic vs. macroscopic structural evolution of SiO2 sols and gels employing a tailor-made fluorescent reporter dye N2 - The short- and long-term structural evolution and aging of sol–gel materials prepared under mild conditions are studied by fluorometry, dynamic light scattering (DLS), 29Si NMR and gravimetry. In combination with the first, a newly developed donor–acceptor-substituted fluorescent probe with two acidophilic sites of different strength and topology is introduced. Its performance in detecting changes in parameters such as polarity, proticity, and pore volume on the microscopic scale is compared to two other dyes and to the macroscopic changes revealed by DLS, NMR and gravimetry. At early stages of the sol–gel process, fluorometry, DLS and NMR reveal similar changes which are typical of the structural evolution of SiO2 sols having different synthesis parameters. During later times of sol aging, DLS and NMR reflect the growth of the network and indicate that all sols approach similar structural equilibria. Fluorometry supports these findings by signalling a gradual decrease in mobile species with high proton activity. The formation of the spanning cluster upon gelation is strongly evident only from DLS results while the local environment of the fluorophore remains largely unchanged. However, the fluorescent dye is able to report microscopic changes even during long-term aging. Drying of the gels with a pronounced contraction of solvated pores is readily observable by fluorometry and gravimetry. During the late reaction stages, the fluorescence properties of the tailor-made dye are still sensitive toward the environment. PY - 2005 DO - https://doi.org/10.1039/b501622c SN - 0959-9428 SN - 1364-5501 VL - 15 IS - 30 SP - 3069 EP - 3083 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-10378 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krahl, T. A1 - Beer, F. A1 - Relling, A. A1 - Gawlitza, Kornelia A1 - Rurack, Knut A1 - Kemnitz, E. T1 - Toward Luminescent Composites by Phase Transfer of SrF2 :Eu3+ Nanoparticles Capped with Hydrophobic Antenna Ligands N2 - Transparent dispersions of hydrophobic SrF2 :Eu3+ nanoparticles in cyclohexane with up to 20% europium were obtained by fluorolytic sol-gel synthesis followed by Phase transfer into cyclohexane through capping with sodium dodecylbenzenesulfonate (SDBS). The particles were characterized by TEM, XRD and DLS as spherical objects with a diameter between 6 and 11 nm in dry state. 1H-13CP MAS NMR experiments revealed the binding of the anionic sulfonate head group to the particle surface. The particles show bright red luminescence upon excitation of the aromatic capping agents, acting as antennas for an Energy transfer from the benzenesulfonate unit to the Eu3+ centers in the particles. This synthesis method overcomes the current obstacle of the fluorolytic sol-gel synthesis that transparent dispersions can be obtained directly only in hydrophilic solvents. To demonstrate the potential of such hydrophobized alkaline-earth fluoride particles, transparent luminescent organic-inorganic composites with 10% SrF2 :Eu3+ embedded into polyTEGDMA, polyBMA, poly-BDDMA and polyD3MA, respectively, were prepared, endowing the polymers with the luminescence features of the nanoparticles. KW - Nanoparticles KW - Fluorides KW - Sol-gel process KW - Organic-inorganic hybrid composites PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508668 DO - https://doi.org/10.1002/cnma.202000058 SP - 1 EP - 11 PB - Wiley AN - OPUS4-50866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Climent Terol, Estela A1 - Hecht, Mandy A1 - Witthuhn, Heike A1 - Gawlitza, Kornelia A1 - Rurack, Knut T1 - Mix‐&‐read determination of Mercury(II) at trace levels with hybrid mesoporous silica materials incorporating fluorescent probes by a simple mix‐&‐load technique N2 - The synthesis, characterization, and application of mesoporous materials containing boron–dipyrromethene (BODIPY) moieties that allow the sensitive and selective detection of HgII in aqueous environments by fluorescence enhancement is reported. For this purpose, BODIPY dye I containing a thia‐aza crown ether receptor as the fluorescent probe for the detection of HgII in aqueous environments is encapsulated into mesoporous materials to avoid self‐quenching or aggregation in water. Determination of HgII is accomplished within a few seconds with high selectivity and sensitivity, reaching a limit of detection of 12 ppt. The determination of trace amounts of HgII in natural waters and in fish extracts is demonstrated by using our sensing material. The incorporation of the material into several μ‐PAD strips yields a portable, cheap, quick, and easy‐to‐handle tool for trace HgII analysis in water. KW - Dyes/pigments KW - Test strips KW - Mesoporous materials KW - Mercury KW - Fluorescence PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-460138 DO - https://doi.org/10.1002/open.201800277 SN - 2191-1363 VL - 7 IS - 12 SP - 957 EP - 968 PB - Wiley-VCH CY - Weinheim AN - OPUS4-46013 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Alnajjar, M. A. A1 - Bartelmeß, Jürgen A1 - Hein, R. A1 - Ashokkumar, Pichandi A1 - Nilam, M. A1 - Nau, W. M. A1 - Rurack, Knut A1 - Hennig, A. T1 - Rational design of boron-dipyrromethene (BODIPY) reporter dyes for cucurbit[7]uril N2 - We introduce herein boron-dipyrromethene (BODIPY) dyes as a new class of fluorophores for the design of reporter dyes for supramolecular host–guest complex formation with cucurbit[7]uril (CB7). The BODIPYs contain a protonatable aniline nitrogen in the meso-position of the BODIPY chromophore, which was functionalized with known binding motifs for CB7. The unprotonated dyes show low fluorescence due to photoinduced electron transfer (PET), whereas the protonated dyes are highly fluorescent. Encapsulation of the binding motif inside CB7 positions the aniline nitrogen at the carbonyl rim of CB7, which affects the pKa value, and leads to a host-induced protonation and thus to a fluorescence increase. The possibility to tune binding affinities and pKa values is demonstrated and it is shown that, in combination with the beneficial photophysical properties of BODIPYs, several new applications of host–dye reporter pairs can be implemented. This includes indicator displacement assays with favourable absorption and emission wavelengths in the visible spectral region, fluorescence correlation spectroscopy, and noncovalent surface functionalization with fluorophores. KW - BODIPY KW - Cucurbituril KW - Fluorescence KW - PH KW - Photoinduced Electron Transfer KW - Supramolecular Chemistry PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-456361 UR - https://www.beilstein-journals.org/bjoc/content/pdf/1860-5397-14-171.pdf DO - https://doi.org/10.3762/bjoc.14.171 SN - 1860-5397 VL - 14 SP - 1961 EP - 1971 PB - Beilstein-Institut CY - Frankfurt a. M. AN - OPUS4-45636 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gotor, Raul A1 - Ashokkumar, Pichandi A1 - Hecht, Mandy A1 - Keil, Karin A1 - Rurack, Knut T1 - Optical pH Sensor Covering the Range from pH 0−14 Compatible with Mobile-Device Readout and Based on a Set of Rationally Designed Indicator Dyes N2 - In this work, a family of pH-responsive fluorescent probes has been designed in a rational manner with the aid of quantum chemistry tools, covering the entire pH range from 0−14. Relying on the boron−dipyrromethene (BODIPY) core, all the probes as well as selected reference dyes display very similar spectroscopic properties with ON−OFF fluorescence switching responses, facilitating optical readout in simple devices used for detection and analysis. Embedding of the probes and reference dyes into hydrogel spots on a plastic strip yielded a test strip that reversibly indicates pH with a considerably small uncertainty of ~0.1 pH units. These strips are not only reusable but, combined with a 3D-printed case that can be attached to a smartphone, the USB port of which drives the integrated LED used for excitation, allows for autonomous operation in on-site or in-the-field applications; the developed Android application software (“app”) further simplifies operation for unskilled users. KW - Fluorescence KW - pH measurement KW - BODIPY KW - Smartphone KW - Test strip PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-422571 DO - https://doi.org/10.1021/acs.analchem.7b01903 SN - 0003-2700 SN - 1520-6882 VL - 89 IS - 16 SP - 8437 EP - 8444 PB - American Chemical Society CY - Washington, D.C., USA AN - OPUS4-42257 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bell, Jérémy A1 - Gawlitza, Kornelia A1 - Rurack, Knut T1 - Die 3D-Mikrofluidik mit molekular geprägten Polymerpartikeln eröffnet neue Möglichkeiten der selektiven Pestizid-Bestimmung in Wasser N2 - 2,4-D ist ein in der Landwirtschaft weitverbreitetes Pflanzenschutzmittel, das Grundwasser kontaminiert, sich innerhalb der Nahrungskette anreichert und Umwelt- und Gesundheitsprobleme verursachen kann. Hier stellen die Autoren ein mikrofluidisches Nachweissystem für die Echtzeitdetektion von 2,4-D in Grund- oder Oberflächenwasser vor. Es basiert auf der Kombination 2,4-D-selektiver, fluoreszierender, molekular geprägter Polymer-(MIP-)Mikropartikel mit einem 3D-mikrofluidischen Extraktions- und Detektionssystem. Messungen vor Ort sollen damit künftig möglich sein. KW - 3D-Mikrofluidik KW - Sensorpartikel KW - MIP KW - Pestizid PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-444781 UR - https://www.labo.de/epaper/LA0318/index.html SN - 0344-5208 IS - 3 SP - 10 EP - 13 PB - WEKA Business Medien GmbH AN - OPUS4-44478 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bell, Jérémy A1 - Gawlitza, Kornelia A1 - Rurack, Knut T1 - Mit Tröpfchen Spielen N2 - Mikrofluidische Systeme sind leistungsstarke analytische Tools mit attraktiven Eigenschaften wie miniaturisierter Größe, geringem Reagenzien und Probenverbrauch, schneller Ansprech- und kurzer Messzeit. Der Bedarf solcher leistungsstarken, miniaturisierten und direkt vor Ort anwendbaren Sensorsysteme steigt kontinuierlich, hauptsächlich durch das Bedürfnis der Gesellschaft, schneller, besser und umfassender über kritische Faktoren im Lebens- und Arbeitsumfeld sowie der Umwelt informiert zu sein. KW - Mikrofluidik KW - Sensorpartikel PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-459120 UR - https://www.git-labor.de/forschung/umwelt/mit-troepfchen-spielen VL - 8 IS - 8 SP - 2 EP - 4 PB - Wiley-VCH Verlag GmbH & Co. KGaA CY - Weinheim, Deutschland AN - OPUS4-45912 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bell, Jérémy A1 - Gawlitza, Kornelia A1 - Rurack, Knut T1 - Playing with Droplets N2 - Microfluidic devices are powerful analytical tools with appealing features such as miniaturized size, low reagent and sample consumption, rapid response and short measurement times. As society wants to be ever better, earlier and more comprehensively informed about critical factors in life, work, and the environment, the demand for powerful measurement devices for use outside of the laboratory constantly increases. KW - Microfluidics KW - Sensory particles PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-459131 UR - https://www.laboratory-journal.com/ VL - 4 SP - 2 EP - 4 PB - Wiley-VCH Verlag GmbH & Co. KGaA CY - Weinheim, Deutschland AN - OPUS4-45913 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Climent Terol, Estela A1 - Hecht, Mandy A1 - Witthuhn, Heike A1 - Gawlitza, Kornelia A1 - Rurack, Knut T1 - Cover profile for the article "Mix‐&‐read determination of Mercury(II) at trace levels with hybrid mesoporous silica materials incorporating fluorescent probes by a simple mix‐&‐load technique" N2 - Invited for this month’s cover picture is the group of Dr. Knut Rurack at the Department of Analytical Chemistry; Reference Materials at the Bundesanstalt fuer Materialforschung und -pruefung (BAM) in Berlin (Germany). The cover picture shows how differences in color and fluorescence on a test strip can be easily read out with a mobile device. Two reference spots Frame the sensitive spot that indicates the presence of trace amounts of HgII below the threshold in a natural water sample. This dipstick contains a hybrid material that combines boron-dipyrromethene (BODIPY) probes sterically loaded into specifically tailored mesoporous silica particles, allowing for ultrasensitive HgII detection through enhanced fluorescence in a few seconds. The applicability in real water samples and fish extracts are also studied. KW - Mercury KW - Fluorescence KW - Dip-stick assay KW - Group profile PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-471267 DO - https://doi.org/10.1002/open.201800231 SN - 2191-1363 VL - 7 IS - 12 SP - 932 EP - 933 PB - Wiley-VCH CY - Weinheim AN - OPUS4-47126 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Climent Terol, Estela A1 - Rurack, Knut T1 - Streifenschnelltest mit ppt-Empfindlichkeit durch Kombination von Elektrochemilumineszenz-Detektion mit Aptamer-gesteuerter Indikatorfreisetzung aus mesoporösen Nanopartikeln N2 - Die Kombination aus elektrogenerierter Chemilumineszenz (ECL) und Aptamer-gesteuerter Indikatorfreisetzung (gAID) aus magnetischen mesoporösen Silica-Nanopartikeln, die in mit Poly(ethylenglycol) und N-(3-Triethoxysilylpropyl) diethanolamin funktionalisiertes Glasfaserpapier eingebettet sind, ermöglichte die Entwicklung eines Schnelltests, mit dem sich Penicillin direkt in verdünnter Milch bis auf 50 +/- 9 ppt in <5 min nachweisen lässt. Die kovalente Bindung der Aptamer-Kappe an das Siliciumdioxid-Gerüst ermöglichte den Verschluss der Poren durch nicht-kovalente elektrostatische Wechselwirkungen mit Oberflächen-Aminogruppen. Die Bindung von Penicillin führte zu einer Faltung des Aptamers, wodurch der zuvor in das Material geladene ECL-Reporter Ru(bpy)32+ freigesetzt wurde und nach lateralem Fluss von einer Smartphone-Kamera nach elektrochemischer Anregung mit einer in einen 3D-gedruckten Halter eingesetzten Siebdruckelektrode detektiert wird. Der Ansatz ist einfach, generisch und bietet Vorteile hinsichtlich Empfindlichkeit, Messunsicherheit und Robustheit gegenüber konventioneller Fluoreszenz- oder elektrochemischer Detektion, insbesondere für Point-of-Need-Analysen anspruchsvoller Matrices und Analyten im Ultraspurenbereich. KW - Schnelltests KW - Elektrochemilumineszenz KW - Aptamere KW - Teststreifen KW - Gesteuerte Freisetzung PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-540205 DO - https://doi.org/10.1002/ange.202110744 VL - 133 IS - 50 SP - 26491 EP - 26501 PB - Wiley-VCH CY - Weinheim AN - OPUS4-54020 LA - deu 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 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 - TY - JOUR A1 - Wan, Wei A1 - Wagner, Sabine A1 - Rurack, Knut T1 - Fluorescent monomers: "bricks" that make a molecularly imprinted polymer "bright" N2 - Molecularly imprinted polymers (MIPs) are potent and established recognition phases in separation and enrichment applications. Because of their robustness, versatility and format adaptability, they also constitute very promising sensing phases, especially when the active sensing element is directly integrated into the MIP. Fluorescent MIPs incorporating fluorescent monomers are perhaps the best developed and most successful approach here. This article reviews the state of the art in this field, discussing the pros and cons of the use of fluorescent dye and probe derivatives as such monomers, the different molecular interaction forces for template complexation, signalling modes and a variety of related approaches that have been realized over the years, including Förster resonance energy transfer processes, covalent imprinting, postmodification attachment of fluorescent units and conjugated polymers as MIPs; other measurement schemes and sensing chemistries that use MIPs and fluorescence interrogation to solve analytical problems (fluorescent competitive assays, fluorescent analytes, etc.) are not covered here. Throughout the article, photophysical processes are discussed to facilitate understanding of the effects that can occur when one is planning for a fluorescence response to happen in a constrained polymer matrix. The article concludes with a concise assessment of the suitability of the different formats for sensor realization. KW - Chemical sensors KW - Fluorescence KW - Molecularly imprinted polymers KW - Dyes KW - Sol-gel PY - 2016 DO - https://doi.org/10.1007/s00216-015-9174-4 SN - 1618-2642 SN - 1618-2650 VL - 408 IS - 7 SP - 1753 EP - 1771 PB - Springer CY - Berlin AN - OPUS4-35830 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartelmeß, Jürgen A1 - Gawlitza, Kornelia A1 - Bartholmai, Matthias A1 - Rurack, Knut T1 - Developments towards the fluorescence based sensing of hazardous gases N2 - Fluorescence based sensing is a versatile approach for the trace analysis outside of the laboratory, requiring suitable sensor materials and their integration into sensing devices. The versatility of fluorophores as probes, especially in terms of the possibility to tailor their optical as well as their recognition properties by synthetic modifications in a wide range, renders them a superior active component for the preparation of optical sensor devices. Recent works at BAM in this field include, for example, the detection of nerve gas agents, illustrating impressively the aforementioned benefits of fluorophores in optical sensing applications. In the interdisciplinary approach presented here, we target hazardous gases such as ammonia, benzene, and hydrogen sulfide, next to others, which pose a major threat to human health and environmental safety and for which the availability of a sensitive and reliable detection method is highly desirable. The dyes presented follow a “turn-on” fluorescence schematic which allows for the selective and sensitive detection of the respective gaseous analyte. The immobilization of the probe in polymeric matrices is then the next step toward the fabrication of a prototype device for molecular sensing. T2 - Colloquium of Optical Spectrometry (COSP) 2017 CY - Berlin, Germany DA - 27.11.2017 KW - Gas sensing KW - Fluorescence KW - KonSens PY - 2017 AN - OPUS4-43209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Garrido, E. A1 - Climent Terol, Estela A1 - Marcos, M. D. A1 - Sancenón, F. A1 - Rurack, Knut A1 - Martínez-Máñez, R. T1 - Dualplex lateral flow assay for simultaneous scopolamine and "cannibal drug" detection based on receptor-gated mesoporous nanoparticles N2 - We report herein the design of a strip-based rapid test utilizing bioinspired hybrid nanomaterials for the in situ and at site detection of the drug scopolamine (SCP) using a smartphone for readout, allowing SCP identification in diluted saliva down to 40 nM in less than 15 min. For this purpose, we prepared a nanosensor based on mesoporous silica nanoparticles loaded with a fluorescent reporter (rhodamine B) and functionalized with bethanechol, a potent agonist of recombinant human muscarinic acetylcholine receptor M2 (M2-AChR). M2-AChR interaction with the anchored bethanechol derivative leads to capping of the pores. The sensing mechanism relies on binding of SCP to M2-AChR resulting in pore opening and delivery of the entrapped rhodamine B reporter. Moreover, the material was incorporated into strips for lateral-flow assays coupled to smartphone readout, giving fast response time, good selectivity, and exceptional sensitivity. In an attempt to a mobile analytical test system for law enforcement services, we have also developed a dualplex lateral flow assay for SCP and 3,4-methylenedioxypyrovalerone (MDPV) also known as the so-called “cannibal drug”. KW - Rapid tests KW - Vor-Ort-Analytik KW - Lateral Flow Assays KW - Scopolamine KW - Gesteuerte Freisetzung KW - Cannibal Drug PY - 2022 DO - https://doi.org/10.1039/d2nr03325a SP - 1 EP - 9 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-55744 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Climent Terol, Estela A1 - Biyikal, Mustafa A1 - Gawlitza, Kornelia A1 - Dropa, T. A1 - Urban, M. A1 - Costero, A. M. A1 - Martínez-Mánez, Ramon A1 - Rurack, Knut T1 - A rapid and sensitive strip-based quick test for nerve agents Tabun, Sarin, and Soman using BODIPY-modified silica materials N2 - Test strips that in combination with a portable fluorescence reader or digital camera can rapidly and selectively detect chemical warfare agents (CWAs) such as Tabun (GA), Sarin (GB), and Soman (GD) and their simulants in the gas phase have been developed. The strips contain spots of a hybrid indicator material consisting of a fluorescent BODIPY indicator covalently anchored into the channels of mesoporous SBA silica microparticles. The fluorescence quenching response allows the sensitive detection of CWAs in the μg m−3 range in a few seconds. KW - Chemical warfare agents KW - Fluorescence KW - Hybrid sensor materials KW - Nerve gases KW - Test strip analysis PY - 2016 DO - https://doi.org/10.1002/chem.201601269 SN - 0947-6539 SN - 1521-3765 VL - 22 IS - 32 SP - 11138 EP - 11142 PB - Wiley CY - Online Library AN - OPUS4-37063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rurack, Knut T1 - Fluorescent mesoporous silicia materials discriminating Ag(l) and Hg (II) T2 - 25th Congress of the Analytical Chemistry Division of the Italian Chemical Society CY - Trieste, Italien DA - 2015-09-13 PY - 2015 AN - OPUS4-33635 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gawlitza, Kornelia A1 - Fischer, Tobias A1 - Rurack, Knut T1 - Chemical functionalization for quantitative spectroscopic labeling on macroscopically flat surfaces N2 - This chapter highlights the application of chemical derivatization (CD) to facilitate the quantification of surface functional groups being an important issue for a wide field of applications. The selective attachment of a chemical label to a surface functional group being afterwards exclusively detectable by a highly sensitive technique overcomes the problem of characterizing low amounts of functional groups on macroscopically flat surfaces. The most frequently employed methods include CD X-ray photoelectron spectroscopy, ultraviolet/visible absorption, and fluorescence spectroscopy, as well as time-of-flight secondary ion mass spectrometry. Herein, the basic conditions for the different techniques regarding the specific surface functional group which need to be quantified are discussed. Additionally, the substrate highly influences the compatibility of the corresponding method. Because not just the quantification but also the preparation of the desired application is important, a summary of different preparation methods for glass, polymer and gold substrates is presented. KW - Chemical derivatization KW - Fluorescence KW - Surface group quantification KW - Time-of-flight secondary ion mass spectrometry KW - UV/vis spectroscopy KW - X-ray photoelectron spectroscopy PY - 2018 SN - 978-0-12-409547-2 DO - https://doi.org/10.1016/B978-0-12-409547-2.13191-9 SP - 1 PB - Elsevier AN - OPUS4-43767 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Climent Terol, Estela A1 - Rurack, Knut T1 - Combining electrochemiluminescence detection with aptamer-gated indicator releasing mesoporous nanoparticles enables ppt sensitivity for strip-based rapid tests N2 - The combination of electrogenerated chemiluminescence (ECL) and aptamer-gated indicator delivering (gAID) magnetic mesoporous silica nanoparticles embedded into glass fibre paper functionalised with poly(ethyleneglycol) and N-(3-triethoxysilylpropyl)diethanolamine allowed the development of a rapid test that detects penicillin directly in diluted milk down to 50 ± 9 ppt in <5 min. Covalent attachment of the aptamer ‘cap’ to the silica scaffold enabled pore closure through non-covalent electrostatic interactions with surface amino groups, while binding of penicillin led to a folding-up of the aptamer thus releasing the ECL reporter Ru(bpy)32+ previously loaded into the material and letting it be detected after lateral flow by a smartphone camera upon electrochemical excitation with a screen printed electrode inserted into a 3D-printed holder. The approach is simple, generic and presents advantages with respect to sensitivity, measurement uncertainty and robustness compared with conventional fluorescence or electrochemical detection, especially for point-of-need analyses of challenging matrices and analytes at ultra-trace levels. KW - Electrochemiluminiscence KW - Hybrid materials KW - Signal amplification KW - Test strip analysis KW - Penicillin PY - 2021 DO - https://doi.org/10.1002/anie.202110744 SN - 1433-7851 SN - 1521-3773 SP - 1 EP - 11 PB - Wiley-VCH CY - Weinheim AN - OPUS4-53447 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rurack, Knut T1 - Combining Fluorescent Probes, Functionalized Surfaces, Tailored Particles and Device Embedding for Robust, Reliable and User-friendly Analytical Assays N2 - Supramolecular chemistry, fluorescence detection, hybrid (nano)materials and device miniaturization are in themselves highly interesting areas of research, yet especially their combination paves the way to (bio)chemical analysis systems that show outstanding performance. The lecture gives an overview of the toolbox of single components developed in BAM’s Chemical and Optical Sensing Division over the years, and how their combination can result in powerful sensors, quick tests and assays. While at the core of a development is the analytical problem, that is, the determination of a certain analyte in a sample of interest with the required sensitivity and selectivity by a specific end user in a given setting, signaling mechanisms, recognition elements, signal transduction modes, materials functionalization, device design and system integration are adequately chosen, tailored and adapted. Examples including molecularly imprinted polymers, hybrid mesoporous nanomaterials, gated indicator release systems, microfluidic devices, test strips and smartphone-based analysis will be presented. T2 - GDCh CY - Chemnitz, Germany DA - 21.06.2018 KW - Fluorescence KW - Particles KW - Rapid tests KW - Device embedding PY - 2018 AN - OPUS4-45640 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rurack, Knut T1 - Molecularly Imprinted Polymers with Integrated Fluorescence as Versatile Biomimetic Sensing Matrices N2 - Molecularly imprinted polymers (MIPs) are an established, versatile and high-performance matrix for the selective separation or enrichment of (bio)chemical species, especially small molecules of biochemical or environmental relevance. MIPs are prepared through the polymerization of a mixture of functional monomers and cross-linkers in the presence of the template with subsequent extraction of the latter. Conceptionally, this process can be seen as mimicking in a strongly accelerated, though single-step manner a biological process such as antibody formation. Because the resulting MIPs contain cavities in their matrix that are complementary in size, shape and electronic/ electrostatic or hydrogen bonding demand to the imprinted target molecule or template, these polymers are frequently termed “artificial antibodies”. Compared to natural antibodies, they are chemically and physically much more robust. Regarding sensitivity and selectivity, however, there is still a gap to bridge before MIPs can fully compete with antibodies. Another favorable aspect that distinguishes MIPs from antibodies is that they can be endowed with an explicit function, allowing the use of MIPs in applications that require more than only an efficient binder. For instance, if specifically designed and polymerizable fluorescent indicators are integrated as functional monomers into a MIP, direct fluorescence sensing can be accomplished. Because MIPs can be prepared in a variety of different formats, their combination with miniaturized or other specific analytical techniques or sensory devices is possible, especially when the transduction mode is light. This presentation will introduce basic design considerations, challenges, limitations and the potential that lies with such sensor materials with some recent examples of our group, targeting various organic oxoanions as analytes. T2 - 8th International Symposium on Bioanalysis, Biomedical Engineering and Nanotechnology CY - Changsha, Hunan, China DA - 25.05.2018 KW - Molecularly imprinted polymers KW - Fluorescence KW - Anion recognition PY - 2018 AN - OPUS4-45641 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -