TY - CONF A1 - Climent Terol, Estela A1 - Wan, Wei A1 - Weller, Michael G. A1 - Rurack, Knut T1 - Novel specific bio-gated hybrid materials and their integration into versatile platforms for advanced sensing applications N2 - Methods for the rapid and sensitive detection of target analytes are gaining importance in medical diagnostics and environmental monitoring, in the security, occupational health and safety as well as food sectors. Among all of the methods employed for rapid tests, lateral flow assays (LFAs) are the most commonly used, and hundreds of test kits based on this technique are available on the market. A major drawback is that most of these capture agents either indicate the analyte only indirectly, and in most cases a second binding agent able to bind directly or indirectly to the analytes is necessary (e.g., a secondary labeled antibody). Furthermore, in certain cases in which the (ultra)trace detection of an analyte is required, the traditional approach of a certain number of probe molecules being conjugated to a particular support is not sufficient. Therefore, novel concepts implementing steps of effective signal amplification are urgently required. Keeping in mind these limitations, we thought that the sensitivity of these systems should be improvable through employment of gated reporter molecule-releasing hybrid nanoparticle materials on novel lateral flow devices. On one hand, the gated sensor material can produce a massive signal amplification, by releasing many reporter molecules only after chemical recognition of a few analyte molecules has taken place in an independent and separate step at the pore openings. On the other hand, the employment of tailored capture materials for the selective interaction with the released reporter molecules in a second arbitrary zone on the strip allows to concentrate or focus the latter for more efficient detection or to create selective multi-spot detection zones, which renders the simultaneous detection of several reporter molecules at the same time in multiplexed detection of various analytes possible. For that purpose, we have prepared several stimuli-responsive materials for small-molecule sensing based on specific interactions between biomolecules such as antibodies with the corresponding analytes for the detection of certain explosives. In order to prepare these bio-capped materials, we have selected silica mesoporous nanoparticles (MSNs) as inorganic support due to their unique properties such as defined void structure, high inner surface area and flexible functionalization chemistry. These MSNs are loaded with a brightly fluorescent indicator dye, and the external surface is subsequently functionalized with suitable molecules able to interact with antibodies, efficiently inhibiting dye release. The opening protocol and delivery of the entrapped dye is reminiscent of a displacement reaction involving the presence of the target analyte, producing a displacement of the biomolecule and allowing the detection of the target analyte. The presentation discusses general aspects of system design as well as analytical performance and highlights the integration into a lateral-flow assay, showing as an example the determination of the explosives TATP, TNT and PETN with fluorescence readout, in single-substance and multiplexing modes. T2 - EBS 2019 CY - Florence, Italy DA - 18.02.2019 KW - Bio-gated hybrid materials KW - Signal amplification KW - Explosives determination KW - Fluorescence KW - Rapid test KW - Dip-stick assay PY - 2019 AN - OPUS4-47920 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -