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As a highly toxic and widely used chemical, phosgene has become a serious threat to humankind and public security because of its potential use by terrorists and unexpected release during industrial accidents. For this reason, it is an urgent need to develop facile, fast, and selective detection methods of phosgene. In this Article, we have constructed a highly selective fluorescent sensor o-Pab for phosgene with a BODIPY unit as a fluorophore and o-phenylenediamine as a reactive site. The sensor o-Pab exhibits rapid response (15 s) in both colorimetric and turn-on fluorescence modes, high selectivity for phosgene over nerve agent mimics and various acyl chlorides and a low detection limit (2.7 nM) in solutions. In contrast to most undistinguishable sensors reported, o-Pab can react with phosgene but not with its substitutes, triphosgene and biphosgene. The excellent discrimination of o-Pab has been demonstrated to be due to the difference in highly reactive and bifunctional phosgene relative to its substitutes. Furthermore, a facile testing paper has been fabricated with poly(ethylene oxide) immobilizing o-Pab on a filter paper for real-time selective monitoring of phosgene in gaseous phase. [ABSTRACT FROM AUTHOR]

Six new metal–organic frameworks (MOFs), namely,[Pb(H2IDC)2(H2O)]n(1), {[Pb(H2IEDC)2)]·3H2O}n(2), [Ca2(HIDC)2(H2O)]n(3), {[Ca2(IEDC)2(H2O)2]·H2O}n(4), {[Cd(HIDC)(H2O)]n(5), and {[Cd2(HIEDC)2·3H2O}n(6) (H3IDC = 4,5-imidazoledicarboxylic acid, H3IEDC = 2-ethyl-1H-imidazole-4,5-dicarboxylicacid) were hydrothermally synthesized and characterized. Single-crystalX-ray diffraction shows the ligand H3IDC is partially deprotonatedwith H2IDC–and HIDC2–forms in three corresponding compounds 1, 3, and 5, meanwhile ligand H3IEDC also presentsdifferent deportonated motifs of H2IEDC–, IEDC3–, and HIEDC2–in 2, 4, and 6, respectively. Moreover,these partially or fully deportonated ligands coordinate in the μ1to μ5manner to generate one-dimensional(1D) → three-dimensional (3D) coordination polymers, displaying10 different coordination modes. Both 1and 2have 3D supramolecular networks assembled via hydrogen bonding interactionsbut different in structure topologies. Complex 1is a1D coordination chain and 2has a two-dimensional (2D)wave layer-like structure with 44topology. Complex 3is a 3D MOF with 310·425·510topology built up from linear 2-connected HIDC2–as a linker and 10-connected tetranuclear metal unit [Ca4(μ2-O)6] as a node. However, complex 4presents a 2D MOF with 36·46·53topology. Different from 3and 4, with the 4-connected binuclear metal unit [Cd(O–C–O)]2as a node, a wave-like 2D MOF with 44topologyin 5based on H3IDC is created. Complex 6shows a 3D coordination framework containing 1D alternatelyarranged hydrophilic channels including (H2O)4clusters and hydrophobic channels partially occupied by ethyl groupsfrom imidazole rings, in which the Cd(II) ion is viewed as a 4-connectednode, and HIEDC2–and μ2-O areregarded as two different linkers, 6showing 42·84topology. Obviously, these results reveal thatthe existence of the substitute groups of 2-position in such 4,5-imidazoledicarboxylateligand plays a critical role in the structural direction of theseMOFs. Meanwhile, the adsorption and photoluminescent properties ofthe selected compounds are investigated. [ABSTRACT FROM AUTHOR]

Novel 3D barcodes with an extraordinarily high encoding capacity are developed through a flexible, accurate, and reproducible method. Here, the three dimensions refer to the size, fluorescence emission wavelength, and intensity of the barcodes. As a proof of concept, a 3D barcode library with an encoding capacity of 100 flow cytometry-distinguishable barcodes is achieved successfully by combining the multiscaled host particles with a set of guest nanoparticles owning to their individual different fluorescent intensity via an ingenious host-guest structure, where fluorescein isothiocyanate and a kind of quantum dots are separately loaded inside. Five-plexed tumor marker detection is further implemented, and the results demonstrate the strong feasibility of 3D barcodes in multiplex assays. [ABSTRACT FROM AUTHOR]