SENSORS: A Novel Lateral Field Excited Acoustic Wave Sensor for Chemical and Biological Agents

目前正在研制敏感和有选择地探测化学剂和一种生物剂的传感器。 传感器结构由压电平台组成，该压电平台涂覆有选择性地吸附感兴趣的化学或生物制剂的膜。 传感器的灵敏度体现在传感器平台中，该传感器平台包括由横向电场激发的石英晶体。 激励电极被放置成与感测表面相对，并且感测膜被直接附接到传感器平台。 这种布置与标准石英微量天平（QCM）形成对比，在标准石英微量天平（QCM）中，感测表面通常涂覆有金膜，并且它提供增加的灵敏度沿着选择性。 这种新型的横向场激励（LFE）QCM所表现出的高灵敏度归因于这样一个事实，即传感器可以测量由吸附的化学或生物制剂引起的传感膜中的电学和机械性质的变化。 LFE-QCM传感器的选择性通过直接在传感膜中进行分子过滤来获得。 在这个特定的项目中，LFE-QCM传感器被设计用于检测两种特定的化学物质和一种生物制剂。 目标化学品是二甲基膦酸酯（DMMP），它模拟VX和G神经毒剂，以及一种有机磷农药，化学上类似于许多其他化学战剂。 生物制剂为E.大肠杆菌O 157：H7，可能出现在食品或水供应。 为了实现所需的化学和生物传感器，研究小组正在探索与LFE-QCM平台和传感膜相关的几个问题。 这些问题包括LFE-QCM平台中的最佳电极几何形状，用于检测水中有机磷酸酯的新型聚合物和二氧化硅膜的开发，以及E.大肠杆菌抗体的传感表面。 国土安全以及环境和工业健康问题决定了必须开发和部署改进的化学和生物传感器。 在各种山梨酸盐选择性膜已经附着到LFE-QCM表面之后，它们将暴露于化学模拟物和生物制剂，以确定传感特性。 预计这些有机磷化合物和E.大肠杆菌可以扩展到其他重要的化学和生物制剂的选择性传感器的开发。 此外，通过与现有的GK-12和REU计划相结合，该项目将有助于教育一些学生和教师谁将参与研究计划。

Sensors for the sensitive and selective detection of chemical agents and a biological agent are being developed. The sensor structure consists of a piezoelectric platform that is coated with a film that selectively sorbs a chemical or biological agent of interest. The sensitivity of the sensor is embodied in the sensor platform, which consists of a quartz crystal that is excited by a lateral electric field. The exciting electrodes are placed opposite to the sensing surface, and the sensing film is attached directly to the sensor platform. This arrangement is in contrast to the standard quartz microbalance (QCM), where the sensing surface is normally coated with a gold film, and it offers increased sensitivity along with selectivity. The high sensitivity exhibited by this novel lateral-field-excited (LFE) QCM is attributed to the fact that the sensor can measure both electrical and mechanical property changes in the sensing film caused by the sorbed chemical or biological agent. The selectivity of the LFE-QCM sensor is obtained by performing molecular filtering directly in the sensing film. In this specific project the LFE-QCM sensor is being designed to detect two specific chemicals and one biological agent. The target chemicals are dimethyl phosponate (DMMP), which simulates VX and G nerve agents, and an organophosphate pesticide that is chemically similar to many other chemical-warfare agents. The biological agent is E. coli O157:H7, which could appear in food or water supplies. In order to realize the desired chemical and biological sensors, the research team is exploring several issues relating to the LFE-QCM platform and the sensing film. These issues include the optimum electrode geometry in the LFE-QCM platform, the development of novel polymer and silica films for the detection of organophosphates in water, and the coupling of E. coli antibodies to the sensing surface. Homeland security as well as environmental and industrial health concerns dictate that improved chemical and biological sensors must be developed and deployed. After various sorbate-selective films have been attached to the LFE-QCM surface, they will be exposed to the chemical simulants and the biological agent in order to determine the sensing properties. It is anticipated that the proposed work on these organo-phosphorus chemicals and E. coli can be extended to development of selective sensors for other significant chemical and biological agents. In addition, by coupling with existing GK-12 and REU programs, this project will contribute to the education of a number of students and teachers who will participate in the research program.