Department of Electrical Engineering, Kwangwoon University, 447-1, Wolgye, Nowon, Seoul, 139-701, Korea.
Anal Chem. 2012 Oct 2;84(19):8240-5. doi: 10.1021/ac3015615. Epub 2012 Sep 14.
Multiple target detection using a cantilever is essential for biosensor, chemical sensor, and electronic nose systems. We report a novel microcantilever array chip that includes four microreaction chambers in a chip, which consequently contains four different functionalized surfaces for multitarget detection. For model tests, we designed microcantilever chips and demonstrated the ability of binding of 2,4-dinitrotoluene (DNT) targets onto four different surfaces. We used peptide receptors that are known to have highly selective binding. By simply using four microreaction chambers, we immobilized DNT specific peptide (HPNFSKYILHQRC; SP), DNT nonspecific peptide (TSMLLMSPKHQAC; NSP), and self-assembled monolayer (SAM) as well as a bare cantilever. After flowing DNT gases through the cantilever chip, we could monitor the four different binding signals simultaneously. The shifts in NSP provided information as a negative control because it contained information of temperature fluctuations and mechanical vibration from gas flow. By utilizing the differential signal of the SP and NSP, we acquired 7.5 Hz in resonant responses that corresponds with 160 part per billion (ppb) DNT concentration, showing the exact binding response by eliminating the inevitable thermal noise, vibration noise, as well as humidity effects on the peptide surface.
使用悬臂梁进行多目标检测对于生物传感器、化学传感器和电子鼻系统至关重要。我们报告了一种新型的微悬臂梁阵列芯片，该芯片在一个芯片中包含四个微反应室，因此包含了用于多目标检测的四个不同的功能化表面。作为模型测试，我们设计了微悬臂梁芯片，并演示了将 2,4-二硝基甲苯 (DNT) 目标物结合到四个不同表面上的能力。我们使用了已知具有高度选择性结合的肽受体。通过简单地使用四个微反应室，我们将 DNT 特异性肽 (HPNFSKYILHQRC; SP)、DNT 非特异性肽 (TSMLLMSPKHQAC; NSP) 和自组装单层 (SAM) 以及裸悬臂梁固定化。在将 DNT 气体流过悬臂梁芯片后，我们可以同时监测四个不同的结合信号。NSP 的位移提供了作为负对照的信息，因为它包含了温度波动和气流引起的机械振动的信息。通过利用 SP 和 NSP 的差分信号，我们获得了与 160 部分每十亿 (ppb) DNT 浓度对应的 7.5 Hz 的共振响应，通过消除不可避免的热噪声、振动噪声以及肽表面的湿度影响，显示出了准确的结合响应。
