Explosive Sensing with Fluorescent Dendrimers: The Role of Collisional Quenching†

TitleExplosive Sensing with Fluorescent Dendrimers: The Role of Collisional Quenching†
Publication TypeJournal Article
Year of Publication2011
AuthorsOlley, David A., Wren Ellen J., Vamvounis George, Fernee Mark J., Wang Xin, Burn P. L., Meredith Paul, and Shaw Paul E.
JournalChemistry of Materials
Date Published09/2010

We have investigated a series of branched fluorescent sensing compounds with thiophene units in the arms and triphenylamine centers for the detection of nitrated model compounds for 2,4,6-trinitrotoluene (TNT) and the plastic explosives taggant 2,3-dimethyl-2,3-dinitrobutane (DMNB). Stern−Volmer measurements in solution show that the fluorescence is more efficiently quenched by nitroaromatic compounds when compared to a non-nitrated quencher, benzophenone. Simple modification of the structure of the sensing compound was found to result in significant changes to the sensitivity and selectivity toward the nitrated analytes. A key result from time-resolved fluorescent measurements showed that the chromophore−analyte interaction was primarily a collisional process. This process is in contrast to conjugated polymers where static quenching dominates, a difference that could offer a potentially more powerful detection mechanism.