College of Architecture & Environment , Sichuan University , Chengdu 610064 , China.
Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry , Sichuan University , Chengdu 610064 , China.
Anal Chem. 2018 Dec 18;90(24):14469-14474. doi: 10.1021/acs.analchem.8b04161. Epub 2018 Nov 30.
Accurate, sensitive, and selective detection of explosives is of vital importance in antiterrorism and homeland security. Fluorescence sensors are prevalent for sensitive and fast in-field explosive detection but are sometimes compromised by accuracy and stability due to the similar structures of explosives, photobleaching, and complex sample matrixes. Herein, we developed a first bimodal methodology capable of both sensitive in-field fluorescence detection and accurate laboratory mass spectrometric quantification of 2,4,6-trinitrotoluene (TNT) by utilizing the characteristic fluorescent and mass spectrometric response of copper nanoparticles (CuNPs). An excellent selectivity was also realized by involving aptamer recognition. The methodology is capable of detecting TNT at subpart per trillion (PPT) levels, with a detection limit of 0.32 pg mL by inductively coupled plasma mass spectrometry (ICPMS) and 0.17 ng mL by fluorimetry. The signal response was accurate and stable for at least 60 days by ICPMS. Thanks to the biospecificity of the aptamer, this bimodal methodology is potentially applicable to a large panel of explosives.
准确、灵敏和选择性地检测爆炸物对于反恐和国土安全至关重要。荧光传感器常用于灵敏、快速的现场爆炸物检测，但由于爆炸物的相似结构、光漂白和复杂的样品基质，其准确性和稳定性有时会受到影响。在此，我们开发了一种双模方法，该方法利用纳米铜颗粒（CuNPs）的特征荧光和质谱响应，既能实现 2,4,6-三硝基甲苯（TNT）的灵敏现场荧光检测，又能进行准确的实验室质谱定量。通过涉及适体识别，还实现了极好的选择性。该方法能够以亚皮克每万亿（PPT）的水平检测 TNT，通过电感耦合等离子体质谱（ICPMS）检测的检出限为 0.32 pg mL，荧光法检测的检出限为 0.17 ng mL。通过 ICPMS 检测，信号响应至少在 60 天内准确且稳定。由于适体的生物特异性，这种双模方法可能适用于大量爆炸物。
