School of Electrical and Electronic Engineering, Yonsei University, Seoul, South Korea.
Biosens Bioelectron. 2013 Dec 15;50:362-7. doi: 10.1016/j.bios.2013.06.034. Epub 2013 Jun 24.
In this paper, we propose a radio-frequency (RF) biosensor platform based on oscillation frequency deviation at 2.4 GHz. Its feasibility is experimentally demonstrated with the well-known biomolecular binding systems such as biotin-streptavidin and deoxyribonucleic acid (DNA) hybridization. For a basic principle of our biosensing system, the impedance of a resonator with the biomolecular immobilization is at first varied so that the corresponding change results in frequency change of an oscillator. Especially, to enhance the sensitivity of the proposed system, a surface acoustic wave (SAW) filter having a high-Q factor (2000) is utilized. From the resulting component, even a small change of oscillation frequency can be transformed into a large output amplitude variation. According to the experimental results, it is found that our system shows the low detectable limit (1 ng/ml) and fast response time (~real-time) for different target biomolecules, i.e. streptavidin and complementary DNA (cDNA). As a result, we find that our device is an effective biosensing system that can be used for a label-free and real-time measurement of the biomolecular binding events.
在本文中，我们提出了一种基于 2.4GHz 频率偏移的射频（RF）生物传感器平台。通过实验证明了其可行性，实验中使用了众所周知的生物分子结合系统，如生物素-链霉亲和素和脱氧核糖核酸（DNA）杂交。我们的生物传感系统的基本原理是，首先改变具有生物分子固定化的谐振器的阻抗，使得相应的变化导致振荡器的频率变化。特别是，为了提高所提出系统的灵敏度，利用了具有高 Q 因子（约 2000）的声表面波（SAW）滤波器。从所得的分量中，即使是振荡频率的微小变化也可以转化为大的输出幅度变化。根据实验结果，发现我们的系统对于不同的靶标生物分子（即链霉亲和素和互补 DNA（cDNA））表现出低检测极限（约 1ng/ml）和快速响应时间（实时）。因此，我们发现我们的设备是一种有效的生物传感系统，可用于生物分子结合事件的无标记和实时测量。
