The most common bulk acoustic wave device used in biosensing applications is the quartz crystal microbalance (QCM), in which a resonant pure shear acoustic wave is excited via electrodes on both major faces of a thin AT-cut quartz plate. For biosensing, the QCM is used to detect the capture of a target by a target-capture film. The sensitivity of the QCM is typically based solely on the detection of mechanical property changes, as electrical property change detection is limited by the electrode on its sensing surface. A modification of the QCM called the lateral field excited (LFE) QCM (LFE-QCM) has been developed with a bare sensing surface as both electrodes are now on a single face of the quartz plate. Compared to the QCM, the LFE-QCM exhibits significantly higher sensitivity to both electrical and mechanical property changes. This paper presents theoretical and experimental aspects of LFE-QCMs. In particular, the presence and strength of the usual and newfound LFE-QCM modes depend on the electrical properties of the film and/or sensing environment. This work also presents examples of experimental setups for measuring the response of an LFE-QCM, followed by results of LFE-QCMs used to detect liquid electrical and mechanical properties, chemical targets, and biological targets. Finally, details are given about the attachment of various target-capture films to the LFE-QCM surface to capture biomarkers associated with diseases such as cancer.

中文翻译：

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横向场激发石英晶体微天平，用于生物传感应用。

在生物传感应用中最常用的体声波设备是石英晶体微天平（QCM），其中通过薄AT切割石英板的两个主面上的电极激发共振纯剪切声波。对于生物传感，QCM用于检测目标捕获膜对目标的捕获。QCM的灵敏度通常仅基于机械性能变化的检测，因为电性能变化检测受其感应表面上的电极限制。由于两个电极现在都位于石英板的一个面上，因此开发了一种称为横向场激发（LFE）QCM（LFE-QCM）的QCM修改形式，它具有裸露的传感表面。与QCM相比，LFE-QCM对电气和机械性能的变化均具有明显更高的灵敏度。本文介绍了LFE-QCM的理论和实验方面。特别是，通常的和新发现的LFE-QCM模式的存在和强度取决于胶片和/或传感环境的电性能。这项工作还提供了用于测量LFE-QCM响应的实验装置的示例，然后介绍了用于检测液体电气和机械性能，化学目标和生物学目标的LFE-QCM的结果。最后，给出了有关将各种靶标捕获膜附着到LFE-QCM表面以捕获与癌症等疾病相关的生物标志物的详细信息。这项工作还提供了用于测量LFE-QCM响应的实验装置的示例，随后是用于检测液体电气和机械性能，化学目标和生物目标的LFE-QCM的结果。最后，给出了有关将各种靶标捕获膜附着到LFE-QCM表面以捕获与癌症等疾病相关的生物标志物的详细信息。这项工作还提供了用于测量LFE-QCM响应的实验装置的示例，随后是用于检测液体电气和机械性能，化学目标和生物目标的LFE-QCM的结果。最后，给出了有关将各种靶标捕获膜附着到LFE-QCM表面以捕获与癌症等疾病相关的生物标志物的详细信息。