RUI: Addressing critical challenges in trace explosives detection through fundamental research in electrochemical science

摘要：通过电化学科学的基础研究解决痕量爆炸物检测方面的现有不足非技术性：今天的恐怖分子正在使用各种威胁手段。没有一种技术可以检测到各种各样的爆炸物。本研究的目的是通过研究一种有前景的电化学传感器技术，解决目前痕量爆炸物检测中存在的检测成本高、灵敏度低、对干扰敏感和检测下限高等不足。研究的目的是通过了解爆炸性蒸气与传感器的反应，同时设计传感器设备结构，以满足现场条件下严格的灵敏度和选择性要求，从而提高前景广阔的电化学传感器技术的性能。与Smiths IONSCAN等机场现有的筛查系统相比，预计探测器成本将降低两个数量级。使用新的信号调理技术同时提高爆炸物检测的灵敏度和选择性的方法有望改变目前增强电化学传感器性能的做法。未知但可能大量的民用用户将受益于筛查威胁的知识。拟议的研究将使安全部队(民用、军事、工业)能够拥有廉价的探测器，用于即时、现场筛查可疑物质或从表面采样中进行痕迹检测。更广泛的应用是很容易设想的--例如，公民参与使用拟议的低成本电化学气体传感器进行广泛的空气质量监测。作为这项研究的一部分，计划了一个有三个主要推动力的紧密结合的外展计划：高中生夏令营、教师培训研讨会和退伍军人工作培训。技术：本研究的目标是解决关键障碍，如高探测器成本、低灵敏度、易受干扰和高探测极限阻碍现场条件下爆炸物的痕量探测和稳健识别。提出了一种基于混合电势的电化学气体传感机制，以解决当前爆炸物检测中的挑战。研究的目标是研究传感器与分析物的相互作用，设计电化学界面，以提高现场条件下筛选爆炸物的灵敏度和选择性，同时降低检测限和成本。方法是：(A)从理论上了解分析物的热分解过程，以提高检测限；(B)研究多相气相催化，以提高灵敏度；(C)探索新的信号调节技术，以在强干扰中提高灵敏度和选择性；(D)研究独特的电化学特征，以提供所需的选择性；(E)实施低成本的纸基传感器平台，以最大限度地降低检测器成本；和(F)独立验证测试结果并在波特兰国际机场进行现场测试。使用新的信号调节技术同时提高爆炸物检测的灵敏度和选择性的方法有望改变目前在增强电化学传感器性能方面的做法。实施纸基爆炸物传感器平台将为新一代电化学传感器铺平道路。研究结果可能导致爆炸物筛查方面的突破，潜在检测下限为百万分之万亿(pg/ml)，特异性为1000：1(每1000个阳性ID中有1个是假的)，并且检测器成本估计降低了两个数量级，所有这些都与金标准气相色谱-质谱仪检测器系统相比。研究结果将是在实施简单和廉价的探测器方面的巨大飞跃，用于即时、现场筛查对广大预期用户至关重要的可疑物质。

Abstract : Addressing the existing deficiencies in trace explosives detection through fundamental research in electrochemical scienceNon-Technical:Terrorists today are using a diverse palette of threats. There is no single technology that can detect a wide variety of explosives. The goal of this research is to address existing deficiencies in trace explosives detection such as high detector cost, low sensitivity, susceptibility to interferences and high detection limits by investigating a promising electrochemical sensor technology. The research objective is to enhance the performance of the promising electrochemical sensor technology by understanding how explosive vapors react with sensors while engineering the sensor device architecture to meet the rigorous sensitivity and selectivity demands in field conditions. A two-order-of-magnitude reduction in detector cost as compared to existing screening systems in airports such as Smiths IONSCAN is envisioned. The approach of using a new signal conditioning technique to concurrently improve sensitivity and selectivity in explosives detection is poised to transform current practices in augmenting electrochemical sensor performance.An unknown but probably large number of civilian users will benefit from the knowledge of screening threats. The proposed research will enable security forces (civilian, military, industrial) to have inexpensive detectors for instant, on-the-spot screening of suspicious substances or trace detection from a surface sampling. Broader uses are easy to envision - e.g., citizen involvement in widespread air quality monitoring using the proposed low-cost electrochemical gas sensors. A cohesive outreach plan with three major thrusts is planned as part of this research: summer camp for high school students, teacher training workshop, and job training for veterans.Technical:The goal of this research is to solve critical barriers such as high detector cost, low sensitivity, susceptibility to interferences, and high detection limits impeding trace detection and robust discrimination of explosives in field conditions. A mixed potential based electrochemical gas sensing mechanism is envisioned to address the current challenges in explosives detection. The research objective is to investigate the sensor-analyte interaction and engineer the electrochemical interface to augment the sensitivity and selectivity while lowering the detection limit and cost in screening explosives under field conditions. The approach is to (a) theoretically understand the thermal decomposition of the analyte to improve the limits of detection; (b) study heterogeneous gas phase catalysis to improve the sensitivity; (c) explore a novel signal conditioning technique to improve the sensitivity and selectivity amidst strong interference; (d) investigate unique electrochemical signature to impart the required selectivity; (e) implement low-cost paper based sensor platform to minimize detector cost; and (f) independently validate the test results and pursue field testing at Portland International Airport.The approach of using a new signal conditioning technique to concurrently improve sensitivity and selectivity in explosives detection is poised to transform current practices in augmenting electrochemical sensor performance. Implementing a paper based explosive sensor platform will pave the way for a new generation of electrochemical sensors. The research results might lead to a breakthrough in explosives screening with potential detection limits of parts per trillion (pg/mL), a 1000:1 specificity (out of every 1000 positive IDs, 1 is false), and an estimated two-order magnitude reduction in detector cost all as compared to the gold standard Gas Chromatography-Mass Spectrometry detector systems. The research results will be a quantum leap in the implementation of simple and inexpensive detectors for instant, on-the-spot screening of suspicious substances vital to a vast number of anticipated users.