Key Laboratory of Organic Optoelectronic and Molecular Engineering, Department of Chemistry, Tsinghua University , Beijing 100084, China.
Advanced Materials Laboratory, Sandia National Laboratories , Albuquerque, New Mexico 87185, United States.
ACS Appl Mater Interfaces. 2017 Jun 14;9(23):20076-20085. doi: 10.1021/acsami.7b04172. Epub 2017 Jun 5.
By incorporating a cationic dye within a metal-organic framework (MOF) through an ion-exchange process, a responsive dye@bio-MOF-1 composite has been synthesized, serving as a dual-emitting platform for enhanced detection of different kinds of nitro-explosives, especially nitroalkanes, nitramines, and nitrate esters. The dye@bio-MOF-1 composite was constructed with free amines on their well-defined cavities, which is essential for the capture of explosives into their confined nanospace. It was observed that the encapsulation of explosives into the constructed dye@bio-MOF-1 composite could dramatically alter the luminescent properties of the dyes as well as the MOF skeletons owing to the size exclusivity and confinement-induced effect. For nitroaromatics, the dye@bio-MOF-1 composite exhibits turn-off responses via fluorescence quenching. Unexpectedly, the composite shows unique turn-on responses for aliphatic nitro-organics via confinement-induced enhancement, demonstrating enhanced ability to detecting different kinds of explosives selectively in aqueous solution. Furthermore, the dye@bio-MOF-1 film was facilely fabricated, making the chemical sensing more convenient and easier to realize the discrimination of the targeted explosives. The dual tunable responses indicate that dye@bio-MOF-1 composites are favorable materials for molecular sensing. On the basis of the host-guest properties of the constructed dye@bio-MOF-1 composite, our work can be further extended to sensing specific analytes with remarkable turn-on sensing properties, in particular those difficult to recognize with conventional methods.
通过离子交换过程将阳离子染料纳入金属有机骨架（MOF）中，合成了一种响应性染料@生物 MOF-1 复合材料，作为增强检测不同类型硝基爆炸物（尤其是硝基烷烃、硝胺和硝酸酯）的双发射平台。染料@生物 MOF-1 复合材料是由其明确的腔体内的游离胺构建而成，这对于将爆炸物捕获到其受限的纳米空间中至关重要。观察到，由于尺寸排他性和受限诱导效应，将爆炸物封装到构建的染料@生物 MOF-1 复合材料中会极大地改变染料和 MOF 骨架的发光性质。对于硝基芳烃，染料@生物 MOF-1 复合材料通过荧光猝灭表现出关闭响应。出乎意料的是，该复合材料对脂肪族硝基有机物表现出独特的开启响应，通过受限诱导增强，显示出在水溶液中选择性检测不同类型爆炸物的增强能力。此外，易于制备染料@生物 MOF-1 薄膜，使化学传感更加方便，更容易实现对目标爆炸物的区分。双可调谐响应表明，染料@生物 MOF-1 复合材料是分子传感的理想材料。基于构建的染料@生物 MOF-1 复合材料的主客体性质，我们的工作可以进一步扩展到具有显著开启感应特性的特定分析物的感应，特别是那些难以用常规方法识别的分析物。
