Nitroaromatic compounds sensing. Synthesis, photophysical characterization and fluorescence quenching of a new amorphous segmented conjugated polymer with diphenylfluorene chromophores

Distyrylbenzene-based segmented conjugated polymers: Synthesis, thin film morphology and chemosensing of hydrophobic and hydrophilic nitroaromatics in aqueous media

“…Thus, we were successful in obtaining polymeric amorphous assemblies of biphenylene [20], terphenylene [21], quaterphenylene [24] and diphenylfluorenylene [25] groups with good film-forming properties that are solution processable and each show similar optical responses either in solution or in solid state. Besides, despite the absence of side chains in the polymer architecture which is usually a condition to obtain soluble aromatic polymeric materials, we found that polymer solubilities are notably enhanced when the aromatic segments are tethered by the meta rather than para positions [25,26]; the same finding has been reported for quaterphenylenes linked with oligo(ethylene glycol) spacers [12]. Finally, the frustrated packing of semi-rigid segments causes void spaces that ease analyte exchange, thus making films of these nonaggregating amorphous luminescent materials good candidates for chemosensing by fluorescence quenching [1,3,[25][26][27][28].…”

Plasmonic-enhanced fluorescent conjugated polymer chemosensor for ultra-sensitive detection of nitroaromatic vapors

“…The development of rapid, sensitive, compound-specific sensors is prevalent in every area of diagnostics research, including defense against unexploded ordnance, improvised explosive devices, and dangerous chemical run-off in our lakes, streams, groundwater, and other waterways [6,8,9,[11][12][13][14][15][16]. While novel explosives continue to be developed, a great majority still utilize traditional energetic compounds such as trinitrotoluene (TNT).…”

“…Thus, the emphasis of much nitroaromatic sensor research is on identifying ways to detect and quantify the presence of this compound and its more prevalent degradation byproducts (e.g. 2,4-and 2,6-dinitrotoluene, DNT) [11,13,[15][16][17]. transducer indicating the presence of nitroaromatic compounds [6, 11-13, 17, 18].…”

“…Generally, sensors are tools that measure and respond to some quantity of input [3,5,7,12,13]. This response can take the form of a physical reaction to the input through [9,10,14,15,26,27], a process of light absorption and emission as will be described in Section 2.2.…”

“…[2-methoxy-5-(2- ethylhexyloxy)-p-phenylenevinylene] (MEH-PPV) has been shown to display a rapid quenching response in the presence of nitroaromatics due to its advantageous optoelectronic properties and electron-rich alkoxy side groups, which provide a conduit for excited state electron diffusion and transfer to the electron-deficient nitroaromatics[6,11,13,15,17,100].Fluorescent conjugated polymers (CJPs) have recently arisen as powerful signal transducers for solution-and vapor-phase chemical and biological sensors due to their advantageous electrochemical properties and flexible chemical composition [119]. One prominent example in recent years has been the detection of NA compounds (e.g.…”