IEEE Trans Biomed Circuits Syst. 2015 Jun;9(3):345-52. doi: 10.1109/TBCAS.2014.2349074. Epub 2014 Oct 9.
This paper proposes a novel RF biosensor that utilizes a frequency synthesizer associated with a microstrip open-loop resonator for label-free biomolecular detection. The RF biosensor consists mainly of a resonance-assisted transducer and a phase locked loop (PLL) circuit. In this work, the performance of the RF biosensor is validated using the well-known biotin-streptavidin binding system. When biotin is bound to streptavidin, the input impedance of the resonator is varied, resulting in a change in the oscillation frequency. The concentration of the streptavidin is ultimately detected by a voltage signal of the PLL's loop filter with simple measurement equipment. According to the experimental results, the RF biosensor has revealed excellent sensitivity ( ~ 61 kHz/ngml(-1)) and a low detection limit ( ~ 1 ng/ml), as well as a rapid response. These results demonstrate that the RF biosensor can be an effective sensing platform for label-free detection in a biomolecular binding system.
本文提出了一种新颖的射频生物传感器，该传感器利用与微带开环谐振器相关联的频率合成器进行无标记生物分子检测。射频生物传感器主要由共振辅助换能器和锁相环（PLL）电路组成。在这项工作中，使用众所周知的生物素-链霉亲和素结合系统验证了 RF 生物传感器的性能。当生物素与链霉亲和素结合时，谐振器的输入阻抗会发生变化，从而导致振荡频率发生变化。最终，通过 PLL 环路滤波器的电压信号检测链霉亲和素的浓度，使用简单的测量设备。根据实验结果，RF 生物传感器具有出色的灵敏度（61 kHz/ngml(-1)）和低检测限（1 ng/ml），以及快速响应。这些结果表明，RF 生物传感器可以成为生物分子结合系统中无标记检测的有效传感平台。
