TY - JOUR A1 - Felbeck, T. A1 - Mundinger, S. A1 - Lezhnina, M.M. A1 - Staniford, M. A1 - Resch-Genger, Ute A1 - Kynast, U.H. T1 - Multifold fluorescence enhancement in nanoscopic fluorophore-clay hybrids in transparent aqueous media JF - Chemistry - A European journal N2 - Valuable emissive properties of organic fluorophores have become indispensable analytical tools in biophotonics, but frequently suffer from low solubilities and radiationless deactivation in aqueous media, that is, in biological ambience as well. In this report, nanoscaled dye–clay hybrids based on laponite, Na0.7{(Li0.3Mg5.5)[Si8O20(OH)4]}, are taken advantage of to solubilize neutral dyes, which are natively not encountered in water. Previously reported efficiency and solubility bottlenecks of such hybrids can to a large extent be overcome by comparably simple chemical measures, as demonstrated here for two prominent examples, the fluorescent dyes Nile Red and Coumarin 153. On controlled co-adsorption of small bifunctional quaternary ammonium ions (Me3N+C2H5OH and Me3N+C2H5NH2) we observed an outright efficiency boost by an order of magnitude, and a 30-fold brightness gain. Even at higher concentrations, transparency and stability of the hybrid dispersions are retained, rendering them useful for employment as optically functional nanoparticles in bioassays and beyond. KW - Biophotonics KW - Clay KW - Fluorescence KW - Hybrids KW - Nanoparticles PY - 2015 DO - https://doi.org/10.1002/chem.201406416 SN - 0947-6539 SN - 1521-3765 VL - 21 IS - 20 SP - 7582 EP - 7587 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-33816 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -