TY - JOUR A1 - Sarma, Dominik A1 - Gawlitza, Kornelia A1 - Rurack, Knut T1 - Polystyrene Core−Silica Shell Particles with Defined Nanoarchitectures as a Versatile Platform for Suspension Array Technology N2 - The need for rapid and high-throughput screening in analytical laboratories has led to significant growth in interest in suspension array technologies (SATs), especially with regard to cytometric assays targeting a low to medium number of analytes. Such SAT or bead-based assays rely on spherical objects that constitute the analytical platform. Usually, functionalized polymer or silica (SiO2) microbeads are used which each have distinct advantages and drawbacks. In this paper, we present a straightforward synthetic route to highly monodisperse SiO2-coated polystyrene core−shell (CS) beads for SAT with controllable architectures from smooth to raspberry- and multilayer-like shells by varying the molecular weight of poly(vinylpyrrolidone) (PVP), which was used as the stabilizer of the cores. The combination of both organic polymer core and a structurally controlled inorganic SiO2 shell in one hybrid particle holds great promises for flexible next-generation design of the spherical platform. The particles were characterized by electron microscopy (SEM, T-SEM, and TEM), thermogravimetry, flow cytometry, and nitrogen adsorption/desorption, offering comprehensive information on the composition, size, structure, and surface area. All particles show ideal cytometric detection patterns and facile handling due to the hybrid structure. The beads are endowed with straightforward modification possibilities through the defined SiO2 shells. We successfully implemented the particles in fluorometric SAT model assays, illustrating the benefits of tailored surface area which is readily available for small-molecule anchoring. Very promising assay performance was shown for DNA hybridization assays with quantification limits down to 8 fmol. KW - core-shell particles KW - shell morphology KW - flow cytometry KW - scanning electron microscopy KW - stabilizer PY - 2016 U6 - https://doi.org/DOI: 10.1021/acs.langmuir.6b00373 SN - 0743-7463 VL - 32 IS - 15 SP - 3717 EP - 3727 PB - American Chemical Society CY - Washington, DC, USA AN - OPUS4-35833 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gawlitza, Kornelia A1 - Climent Terol, Estela A1 - Biyikal, Mustafa A1 - Witthuhn, Heike A1 - Rurack, Knut T1 - Mesoporous silica materials incorporating BODIPY dyes as a versatile system for the trace detection of hazardous chemical species N2 - There is significant contamination of our water resources and an accelerating accumulation of hazardous species in the aquatic biosphere. Whether for instance mercury as a contaminant constantly released from a multitude of industrial processes or chemical warfare agents (CWAs) such as Tabun (GA), Sarin (GB) or Soman (GD) as highly toxic remnants of World War II, released from dumped containers upon their progressive corrosion, are concerned such hazards can cause serious problems to human health even at low concentration and monitoring them becomes increasingly essential. Conclusively, it is necessary to develop sensors for such hazards that combine high sensitivity, good selectivity, fast responses and can dispense with complex instrumentation. Here, we present SBA-15-type mesoporous silica materials containing boron–dipyrromethene (BODIPY) probes in their pore systems that allow for the sensitive and selective detection of the two target analytes CWAs and Hg2+ in natural waters via a change in the optical properties. In case of Hg2+, the BODIPY dye is directly adsorbed on the (inner and outer) surface of the highly porous material and coordinates the metal ion, leading to an enhancement of fluorescence with a limit of detection (LOD) of 15 ppt. Using the same silica material but incorporating a covalently attached BODIPY dye, the CWAs GA, GD and GB can be detected via fluorescence quenching induced by an intraannular cyclization. The obtained LOD in natural waters is in the pM range and hence below the Maximum Permissible Concentrations for CWAs in drinking water. Aspects of system design as well as application in water and food analysis (fish extracts) will be presented. T2 - Rapid Methods Europe (RME) 2016 CY - Amsterdam, The Netherlands DA - 07.11.2016 KW - Mesoporous silica materials KW - Sensor materials KW - Fluorescence sensors PY - 2016 AN - OPUS4-38182 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gawlitza, Kornelia A1 - Climent Terol, Estela A1 - Biyikal, Mustafa A1 - Witthuhn, Heike A1 - Rurack, Knut T1 - Mesoporous silica materials incorporating BODIPY dyes as a versatile system for the trace detection of hazardous chemical species N2 - There is significant contamination of our water resources and an accelerating accumulation of hazardous species in the aquatic biosphere. Whether for instance mercury as a contaminant constantly released from a multitude of industrial processes or chemical warfare agents (CWAs) such as Tabun (GA), Sarin (GB) or Soman (GD) as highly toxic remnants of World War II, released from dumped containers upon their progressive corrosion, are concerned such hazards can cause serious problems to human health even at low concentration and monitoring them becomes increasingly essential. Conclusively, it is necessary to develop sensors for such hazards that combine high sensitivity, good selectivity, fast responses and can dispense with complex instrumentation. Here, we present SBA-15-type mesoporous silica materials containing boron–dipyrromethene (BODIPY) probes in their pore systems that allow for the sensitive and selective detection of the two target analytes CWAs and Hg2+ in natural waters via a change in the optical properties. In case of Hg2+, the BODIPY dye is directly adsorbed on the (inner and outer) surface of the highly porous material and coordinates the metal ion, leading to an enhancement of fluorescence with a limit of detection (LOD) of 15 ppt. Using the same silica material but incorporating a covalently attached BODIPY dye, the CWAs GA, GD and GB can be detected via fluorescence quenching induced by an intraannular cyclization. The obtained LOD in natural waters is in the pM range and hence below the Maximum Permissible Concentrations for CWAs in drinking water. Aspects of system design as well as application in water and food analysis (fish extracts) will be presented. T2 - Rapid Methods Europe (RME) 2016 CY - Amsterdam, The Netherlands DA - 07.11.2016 KW - Mesoporous silica materials KW - Sensor materials KW - Fluorescence materials PY - 2016 AN - OPUS4-38183 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo A1 - Gawlitza, Kornelia A1 - Banach, Ulrich A1 - Noske, Reinhard A1 - Rurack, Knut A1 - Bartholmai, Matthias T1 - Gas standards for the calibration of novel fluorescence sensors for ammonia N2 - Ammonia and its conversion product ammonium have a strong negative impact on human health and ecosystems. Most ammonia measurements in ambient air are performed in the molar fraction range (0.5 to 500) nmol/mol. There is a need for reliable traceable ammonia gas standards as well as in situ analytical procedures for the monitoring of ammonia in ambient air. The permeation method is an effective tool for dynamically generating precise gas standards with a low uncertainty in the concentration range of a few nmol/mol to several µmol/mol in an inert carrier gas, e. g. pure nitrogen or purified ambient air. Here, we present our ammonia gas standard generator as well as results of the characterisation of its individual components supporting the uncertainty assessment according to GUM for stable gas concentrations in this range. In order to detect ammonia in the nmol/mol-range, a suitable sensor has to be developed. In this contribution, we therefore additionally present first approaches on the development of such a sensor using optical fluorescence as transduction mechanism due to its intrinsically high sensitivity and high spatial resolution. Incorporation of a fluorescent dye, which shows fluorescence enhancement in the presence of ammonia, into a polymer matrix allows to reversibly recognize low amounts of ammonia. It can be concluded that fluorescence sensor is a robust tool for measurements of ammonia; however it needs calibration for the planed use. T2 - MetNH3-workshop on the progress in ammonia metrology CY - Braunschweig, Germany DA - 24.02.2016 KW - Ammonia KW - Fluorescence sensor KW - Permeation KW - Test gas generation PY - 2016 AN - OPUS4-35810 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 U6 - 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 -