Triphenylbenzene Sensor for Selective Detection of Picric Acid

Abstract

A C -symmetric triphenylbenzene based photoluminescent compound, 1,3,5-tris(4'-(N-methylamino)phenyl) benzene ([NHMe]TAPB), has been synthesized by mono-N-methylation of 1,3,5-tris(4'-aminophenyl) benzene (TAPB) and structurally characterized. [NHMe]TAPB acts as a selective fluorescent sensor for picric acid (PA) with a detection limit as low as 2.25 ppm at a signal to noise ratio of 3. Other related analytes (i.e. TNT, DNT and DNB) show very little effect on the fluorescence intensity of [NHMe]TAPB. The selectivity is triggered by proton transfer from picric acid to the fluorophore and ground-state complex formation between the protonated fluorophore and picrate anion through hydrogen bonding interactions. The fluorescence lifetime measurements reveal static nature of fluorescence quenching.

Protonation- and electrostatic-interaction-based fluorescence probes for the selective detection of picric acid (2,4,6-trinitrophenol) – an explosive material

“…Also, instead of PET mechanism operative in case of probe 10a, here proton transfer is the actual quenching mechanism. The quenching efficiency of 10b 42 was in between probes 10a and 10c and was in order of basicity of amine nitrogen. The emission spectrum of 10b showed 85% quenching of the emission maxima with 20 equivalents of PA with a detection limit of 9.82 μM.…”

1,3,5-Triphenylbenzene: a versatile photoluminescent chemo-sensor platform and supramolecular building block

“…The fully N-methyl substituted uorophore 3 has been synthesized by the reaction of 1 with excess methyl iodide in basic medium. 42 Fluorophores 2 and 3 do not form the supramolecular structures, as conrmed from their single crystal structures (Scheme 1). It is important to note that the substitution of N-H groups with N-methyl causes a sizeable red-shi to the absorption and photoluminescence bands of 1 (Fig.…”

A New Compound for Sequential Sensing of Picric Acid and Aliphatic Amines: Physicochemical Details and Construction of Molecular Logic Gates

“…There are numerous small molecule sensors as well to detect PA with low LOD. [42][43][44][45][46][47][48][49][50][51][52][53][54][55][56] Zinc oxide nanomaterials and fluorescent quantum dots were also helpful in PA detection. [57,58] The fluorescent outputs due to the sensing mechanisms were effectively used to prepare logic based devices in some cases.…”