Jin Xiaoxia, Huang Yue, Mason Andrew, Zeng Xiangqun
Department of Chemistry, Oakland University, Rochester, Michigan 48309-4401, USA.
Anal Chem. 2009 Jan 15;81(2):595-603. doi: 10.1021/ac8018697.
Multichannel Monolithic Quartz Crystal Microbalance (MQCM), in which an array of electrodes is fabricated on a monolithic quartz wafer, is a very attractive approach for miniaturization using Micro-Electro-Mechanical Systems(MEMS) technology for high throughput chemical or biological sensor systems. In this paper, we demonstrate and validate a monolithic QCM sensor array for gas detections. The monolithic QCM sensor array chip was fabricated using a simple, straightforward method. Four pairs QCM electrodes on a single AT-cut 10 MHz quartz plate were fabricated in both symmetric and asymmetric designs. Their resonance and sensing properties were thoroughly characterized and compared with a single regular QCM under the same conditions by using parallel multichannel QCM instruments. It is confirmed that each QCM in the MQCM behaves like an independent oscillator that responds to mass and/or viscosity change. Various factors that may affect the MQCM performance, such as the fabrication design, the numbers of oscillated electrodes in one MQCM, and the concentration of target analytes, were studied. Finally, the MQCM electrodes were selectively coated with an assortment of sensing films (ionic liquids (BMICS, BMIBF(4)) and conductive polymer poly(vinyl ferrocene) (PVF)). Their applications capabilities for classification and detection of Volatile Organic Compounds (VOCs, i.e., ethanol, CH(2)Cl(2), hexane) and water were studied. Our results show that the single-chip, multichannel QCM is a feasible and promising technology for a miniaturized, highly sensitive multianalysis system that can lead to substantial reductions in cost, analysis time, and sample volume.
多通道单片式石英晶体微天平（MQCM）是一种极具吸引力的方法，它通过微机电系统（MEMS）技术在单片石英晶圆上制造电极阵列，以实现高通量化学或生物传感器系统的小型化。在本文中，我们展示并验证了一种用于气体检测的单片式QCM传感器阵列。该单片式QCM传感器阵列芯片采用简单直接的方法制造。在单个AT切割的10 MHz石英板上制作了四对QCM电极，采用了对称和不对称两种设计。通过使用并行多通道QCM仪器，在相同条件下对它们的共振和传感特性进行了全面表征，并与单个常规QCM进行了比较。证实了MQCM中的每个QCM都表现得像一个独立的振荡器，对质量和/或粘度变化做出响应。研究了可能影响MQCM性能的各种因素，如制造设计、一个MQCM中振荡电极的数量以及目标分析物的浓度。最后，在MQCM电极上选择性地涂覆了各种传感膜（离子液体（BMICS、BMIBF₄）和导电聚合物聚（乙烯基二茂铁）（PVF））。研究了它们对挥发性有机化合物（VOCs，即乙醇、CH₂Cl₂、己烷）和水的分类和检测应用能力。我们的结果表明，单芯片、多通道QCM是一种可行且有前景的技术，可用于小型化、高灵敏度的多分析系统，能够大幅降低成本、分析时间和样品体积。
