Real-time, label-free, all-electrical detection of Salmonella typhimurium using lead titanate zirconate/gold-coated glass cantilevers at any relative humidity
Real-time, label-free, all-electrical detection of Salmonella typhimurium using lead titanate zirconate/gold-coated glass cantilevers at any relative humidity
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DOI：
10.1016/j.snb.2007.02.030
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发表时间：
2007-08-08
影响因子：
8.4
通讯作者：
Shih, Wei-Heng
中科院分区：
文献类型：
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作者：
Zhu, Qing;Shih, Wan Y.;Shih, Wei-Heng
我们已经检查了非绝缘PZT/镀金玻璃悬臂梁实时，无标签检测鼠伤寒沙门氏菌在任何相对湿度下的部分浸渍。PZT/镀金玻璃悬臂梁由0.127 mm厚、约0.8 mm长、2 mm宽的PZT层与0。15mm厚的镀金玻璃层，用3.0 mm长的镀金玻璃尖端进行检测。我们通过在节点处放置水位来证明这一点。在相对湿度为20%或更高时，在距离金玻璃尖端自由端约0.8 mm处存在一个1/ 2h窗口，在此窗口内，尽管由于蒸发引起水位变化，共振频率仍保持稳定。通过将悬臂倾斜到它们的节点上，我们就能做到实时。在任何相对湿度下，无需背景共振频率校正的无标签检测。部分浸出的PZT/镀金玻璃悬臂梁具有质量检测灵敏度，δ m/ δ f= -5 × 10(-11) g/Hz，在2ml液体中检测浓度灵敏度为5 × 10(3)个细胞/ml。这比5mhz的QCM要低两个数量级。它也比感染剂量低两个数量级，比商用猛禽传感器的检测极限低一个数量级。(C) 2007 Elsevier B.V.版权所有
We have examined non-insulated PZT/gold-coated glass cantilevers for real-time, label-free detection of Salmonella typhimurium by partial dipping at any relative humidity. The PZT/gold-coated glass cantilevers consisted of a 0.127 mm-thick PZT layer about 0.8 mm long, 2 mm wide bonded to a 0. 15 mm-thick gold-coated glass layer with a 3.0 mm-long gold-coated glass tip for detection. We showed that by placing the water level at the nodal point. about 0.8 mm from the free end of the gold-glass tip, there was a 1/2-h window in which the resonance frequency was stable despite the water level change due to evaporation at 20% relative humidity or higher. By dipping the cantilevers to their nodal point, we were able to do real-time. label-free detection without background resonance frequency corrections at any relative humidity. The partially dipped PZT/gold-coated Glass cantilever exhibited mass detection sensitivity, Delta m/Delta f= -5 x 10(-11) g/Hz, and a detection concentration sensitivity, 5 x 10(3) cells/ml in 2 ml of liquid. which was about two orders of magnitude lower than that of a 5 MHz QCM. It was also about two orders of magnitude lower than the infectious dose and one order of magnitude lower that the detection limit of a commercial Raptor sensor. (C) 2007 Elsevier B.V. All rights reserved.