Experimental and Numerical Studies of Cantilever Sensors

现有的检测淡水中重金属的方法需要收集样本并送到专门的实验室进行分析。这样的程序既耗时又昂贵。有一天，含有能够同时检测几种分析物的微悬臂传感器阵列的便携式设备可以用于现场对水进行完整的重金属分析，快速、经济有效，并且只需最少的用户培训。微悬臂传感器是一种小悬臂，长约400微米，宽约50微米，厚约1微米，功能齐全，可接受特定的目标分析物。由于它们的体积很小，数百个悬臂可以安装在一个一角硬币大小的区域内。虽然悬臂式传感器为实现上述目标提供了所有必要的标准，但它们的重复性阻碍了它们应用于商业设备。这项应用的主要目标是，利用实验观察与数值模拟和模拟的创新组合，通过以下方式调查影响悬臂式传感器重现性的因素：探索材料科学问题，如用于锚定传感层的薄Au膜的形貌；利用流体动力学模拟了解分析物如何在传感器单元内流动；以及研究用于检测特定重金属的新型杯芳烃传感层的主/客体反应。

Existing methods for detecting heavy metals in fresh water require samples be collected and sent to specialized laboratories to be analyzed. Such a procedure is time consuming and expensive. Portable devices containing arrays of microcantilever sensors capable of detecting several analytes at one time could, one day, be used for performing a complete heavy metal analysis of water onsite, quickly, cost effectively, and with minimal user training. Microcantilever sensors are small cantilevers approximately 400 microns long, 50 microns wide, and 1 micron thick functionalized to be receptive to specific target analyte. Because of their small size, hundreds of cantilevers can be incorporated in an area the size of a dime. Although cantilever sensors offer all the necessary criteria for satisfying the above goal, their reproducibility has prevented them from being implemented into commercial devices. The principle objective of this application is to investigate, using an innovative combination of experimental observations and numerical modeling and simulations, the factors that affect the reproducibility of cantilever sensors by: exploring the materials science issues such as the morphology of the thin Au film used to anchor the sensing layer; understanding how analyte flows within the sensor cell using fluid dynamics simulations; and studying the host/guest reactions of new calixarene sensing layers designed to detect specific heavy metals.