AlN-based BAW resonators with CNT electrodes for gravimetric biosensing
AlN-based BAW resonators with CNT electrodes for gravimetric biosensing
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DOI：
10.1016/j.snb.2011.09.083
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发表时间：
2011-12-15
影响因子：
8.4
通讯作者：
Lu, J. R.
中科院分区：
文献类型：
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作者：
Garcia-Gancedo, L.;Zhu, Z.;Lu, J. R.
固体安装谐振器（smr）的顶部碳纳米管（CNTs）表面涂层可以兼作电极和传感层。通过与具有顶部金属电极的相同器件直接比较，研究了碳纳米管对谐振器频率响应的影响。研究发现，碳纳米管在谐振器上引入的质量负荷显著减少，这些器件表现出更高的质量因子Q(>2000，相比之下，金属电极器件的质量因子为1000)，这通过允许跟踪较小的频率移来提高器件的重力灵敏度。在谐振器顶部加载不同浓度的蛋白质溶液，研究其对物理吸附涂层质量负载的响应。结果表明，与金属薄膜电极相比，使用碳纳米管作为顶电极的谐振器在给定负载下表现出更高的频率变化(类似于0.25 MHz cm(2) ng(-1))，这是由于碳纳米管电极的质量更低，与金属薄膜电极相比，它们的活性表面积更高。因此，可以得出结论，在谐振器上使用碳纳米管电极作为重力生物传感器是对通常使用的金属电极的重大改进。(C) 2011 Elsevier B.V.版权所有
Solidly mounted resonators (SMRs) with a top carbon nanotubes (CNTs) surface coating that doubles as an electrode and as a sensing layer have been fabricated. The influence of the CNTs on the frequency response of the resonators was studied by direct comparison to identical devices with a top metallic electrode. It was found that the CNTs introduced significantly less mass load on the resonators and these devices exhibited a greater quality factor, Q (>2000, compared to similar to 1000 for devices with metal electrodes), which increases the gravimetric sensitivity of the devices by allowing the tracking of smaller frequency shifts. Protein solutions with different concentrations were loaded on the top of the resonators and their responses to mass-load from physically adsorbed coatings were investigated. Results show that resonators using CNTs as the top electrode exhibited a higher frequency change for a given load (similar to 0.25 MHz cm(2) ng(-1)) compared to that of a metal thin film electrode (similar to 0.14 MHz cm(2) ng(-1)), due to the lower mass of the CNT electrodes and their higher active surface area compared to that of a thin film metal electrode. It is therefore concluded that the use of CNT electrodes on resonators for their use as gravimetric biosensors is a significant improvement over metallic electrodes that are normally employed. (C) 2011 Elsevier B.V. All rights reserved.