Over the last decade a great deal of interest has been raised in applications of Microelectromechanical Sensors [MEMS] for the detection of biological molecules and to the study of their forces of interaction. Experiments in these areas have included Force Spectroscopy (Chemical Force Microscopy), MEMS patch clamp technology, and surface stress sensors. All of these technologies suffer from limitations on temporal response and involve devices with active surface areas that are large compared to molecular dimensions. Biofunctionalized nanoelectromechanical systems (BioNEMS) have the potential to overcome both of these hurdles, offering important new prospects for single-molecule force assays that are amenable to large scale integration. Results are presented here on the characterization of piezoresistive silicon cantilevers with applications to BioNEMS devices. The cantilevers were characterized by studying their response in gaseous ambients under a number of drive conditions including magnetic, piezoelectric, and thermal actuation, in addition to passive detection of the thermomechanical response. The measurements were performed at liquid helium temperature, at room temperature, and over a range of pressures (atmospheric pressure to 30mT). Theoretical studies have been performed on the response of these devices to Brownian fluctuations in fluid, on the feasibility of these devices as surface stress sensors, and on improvements in device design as compared to piezoresistive surface stress sensors currently discussed in the literature. The devices were encapsulated in microfluidics and measurements were performed to show the noise floor in fluid. The piezoresistive response of the device in fluid was shown through the use of pulsatory fluidic drive. As a proof of concept, biodetection experiments are presented for biotin labeled beads. The biofunctionalization for the latter experiment was performed entirely within the microfluidics. A discussion of how these experiments can be extended to other cells, spores, and molecules is presented.ud
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机译：在过去的十年中，人们对微机电传感器[MEMS]在检测生物分子及其相互作用力方面的应用引起了极大的兴趣。这些领域的实验包括力谱法（化学力显微镜），MEMS膜片钳技术和表面应力传感器。所有这些技术都受到时间响应的限制，并且涉及具有比分子尺寸大的有效表面积的器件。生物功能化的纳米机电系统（BioNEMS）具有克服这两个障碍的潜力，为适合大规模集成的单分子力测定法提供了重要的新前景。本文介绍了压阻硅悬臂的表征及其在BioNEMS器件中的应用结果。悬臂的特点是，除了被动检测热机械响应外，还研究了它们在气态环境中在多种驱动条件下的响应，这些条件包括磁，压电和热驱动。测量是在液氦温度，室温和一定压力范围（大气压至30mT）下进行的。与这些文献中目前讨论的压阻表面应力传感器相比，已经对这些器件对流体的布朗波动的响应，这些器件作为表面应力传感器的可行性以及器件设计的改进进行了理论研究。将该装置封装在微流体中，并进行测量以显示流体中的本底噪声。通过使用脉动流体驱动显示了器件在流体中的压阻响应。作为概念的证明，提出了针对生物素标记的珠的生物检测实验。后一个实验的生物功能化完全在微流体中进行。讨论了如何将这些实验扩展到其他细胞，孢子和分子。 ud
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