Xu Miao, Han Ji-Min, Wang Chen, Yang Xiaomei, Pei Jian, Zang Ling
Department of Materials Science and Engineering, University of Utah , 36 South Wasatch Drive, Salt Lake City, Utah 84112, United States.
ACS Appl Mater Interfaces. 2014 Jun 11;6(11):8708-14. doi: 10.1021/am501502v. Epub 2014 May 19.
Trace vapor detection of hydrogen peroxide (H2O2) represents a practical approach to nondestructive detection of peroxide-based explosives, including liquid mixtures of H2O2 and fuels and energetic peroxide derivatives, such as triacetone triperoxide (TATP), diacetone diperoxide (DADP), and hexamethylene triperoxide diamine (HMTD). Development of a simple chemical sensor system that responds to H2O2 vapor with high reliability and sufficient sensitivity (reactivity) remains a challenge. We report a fluorescence ratiometric sensor molecule, diethyl 2,5-bis((((4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)oxy)carbonyl)amino)terephthalate (DAT-B), for H2O2 that can be fabricated into an expedient, reliable, and sensitive sensor system suitable for trace vapor detection of H2O2. DAT-B is fluorescent in the blue region, with an emission maximum at 500 nm in the solid state. Upon reaction with H2O2, DAT-B is converted to an electronic "push-pull" structure, diethyl 2,5-diaminoterephthalate (DAT-N), which has an emission peak at a longer wavelength centered at 574 nm. Such H2O2-mediated oxidation of aryl boronates can be accelerated through the addition of an organic base such as tetrabutylammonium hydroxide (TBAH), resulting in a response time of less than 0.5 s under 1 ppm of H2O2 vapor. The strong overlap between the absorption band of DAT-N and the emission band of DAT-B enables efficient Förster resonance energy transfer (FRET), thus allowing further enhancement of the sensing efficiency of H2O2 vapor. The detection limit of a drop-cast DAT-B/TBAH film was projected to be 7.7 ppb. By combining high sensitivity and selectivity, the reported sensor system may find broad application in vapor detection of peroxide-based explosives and relevant chemical reagents through its fabrication into easy-to-use, cost-effective kits.
过氧化氢（H₂O₂）的痕量蒸汽检测是一种对基于过氧化物的炸药进行无损检测的实用方法，这些炸药包括H₂O₂与燃料的液体混合物以及高能过氧化物衍生物，如三丙酮三过氧化物（TATP）、二丙酮二过氧化物（DADP）和六亚甲基三过氧化二胺（HMTD）。开发一种能以高可靠性和足够灵敏度（反应性）响应H₂O₂蒸汽的简单化学传感器系统仍然是一项挑战。我们报道了一种用于H₂O₂的荧光比率传感器分子，2,5-双（（（（4-（4,4,5,5-四甲基-1,3,2-二氧硼杂环戊烷-2-基）苄基）氧基）羰基）氨基）对苯二甲酸二乙酯（DAT-B），它可以制成一种适用于H₂O₂痕量蒸汽检测的便捷、可靠且灵敏的传感器系统。DAT-B在蓝色区域有荧光，固态下最大发射波长为500 nm。与H₂O₂反应后，DAT-B转变为电子“推挽”结构的2,5-二氨基对苯二甲酸二乙酯（DAT-N），其发射峰位于较长波长处，中心波长为574 nm。通过添加有机碱如氢氧化四丁铵（TBAH），可以加速芳基硼酸酯的这种H₂O₂介导的氧化反应，在1 ppm的H₂O₂蒸汽下响应时间小于0.5秒。DAT-N的吸收带与DAT-B的发射带之间有很强的重叠，能够实现高效的Förster共振能量转移（FRET），从而进一步提高H₂O₂蒸汽的传感效率。预计滴铸的DAT-B/TBAH薄膜的检测限为7.7 ppb。通过结合高灵敏度和高选择性，所报道的传感器系统通过制成易于使用、成本效益高的试剂盒，可能在基于过氧化物的炸药和相关化学试剂的蒸汽检测中得到广泛应用。
