Tanwar Arvin Sain, Iyer Parameswar Krishnan
Department of Chemistry and Centre for Nanotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
ACS Omega. 2017 Aug 10;2(8):4424-4430. doi: 10.1021/acsomega.7b00765. eCollection 2017 Aug 31.
A water-soluble nonfluorescent cationic conjugated polyelectrolyte poly(1,1'-((1,4-phenylenebis(oxy))bis(propane-3,1-diyl))bis(pyridin-1-ium)bromide) (PPPy) was specifically synthesized via an economical method of oxidative coupling polymerization in high yields. PPPy selectively recognized nitroexplosive picric acid (PA) by fluorescence "turn-on" in the presence of closely related nitroexplosive compounds, namely, 2,4,6-trinitrotoluene, 2,4-dinitrophenol, and 4-nitrophenol via fluorescence indicator displacement assay (IDA) technique in water at pH 7.0. The polymer PPPy was characterized by NMR spectroscopy, gel permeable chromatography, UV-vis spectroscopy. The polymer PPPy forms an electrostatic complex with uranine dye. This ensemble scheme was utilized to detect PA with a limit of detection value of 295 nM (solution state) and 0.22 ppm (vapor state) through IDA, a phenomenon that is very different from the widely reported Förster resonance energy transfer, photoinduced electron transfer, ground-state charge transfer and inner filter effect based probes used for nitroexplosive PA detection.
通过经济的氧化偶联聚合法高产率地特异性合成了一种水溶性非荧光阳离子共轭聚电解质聚（1,1'-（（1,4-亚苯基双（氧基））双（丙烷-3,1-二基））双（吡啶-1-鎓）溴化物）（PPPy）。在pH 7.0的水中，PPPy通过荧光指示剂置换分析（IDA）技术，在密切相关的硝基炸药化合物（即2,4,6-三硝基甲苯、2,4-二硝基苯酚和4-硝基苯酚）存在下，通过荧光“开启”选择性识别硝基炸药苦味酸（PA）。通过核磁共振光谱、凝胶渗透色谱、紫外可见光谱对聚合物PPPy进行了表征。聚合物PPPy与尿酸染料形成静电复合物。利用这种整体方案通过IDA检测PA，检测限为295 nM（溶液状态）和0.22 ppm（蒸汽状态），这一现象与广泛报道的用于硝基炸药PA检测的基于Förster共振能量转移、光致电子转移、基态电荷转移和内滤效应的探针非常不同。
