Department of Electronic Engineering, School of Internet of Things Engineering, Jiangnan University, Wuxi 214122, China.
Biosensors (Basel). 2021 Nov 26;11(12):480. doi: 10.3390/bios11120480.
Due to the increasing number of diabetic patients, early monitoring of glucose levels is particularly important; therefore, glucose biosensors have attracted enormous attention from researchers. In this paper, we propose a glucose microwave biosensor based on RFID and achieve a non-contact measurement of the concentration of glucose solutions. The Reader is a complementary split-ring resonator (CSRR), and the Tag is comprised of a squared spiral capacitor (SSC). A polydimethylsiloxane microfluidic quantitative cavity with a volume of 1.56 μL is integrated on the Tag to ensure that the glucose solution can be accurately set to the sensitive area and fully contacted with the electromagnetic flux. Because the SSC exhibits different capacitances when it contacts glucose solutions of different concentrations, changing the resonant frequency of the CSRR, we can use the relationship to characterize the biosensing response. Measurement results show that bare CSRR and RFID-based biosensors have achieved sensitivities of 0.31 MHz/mg·dL and 10.27 kHz/mg·dL, and detection limits of 13.79 mg/dL and 1.19 mg/dL, respectively, and both realize a response time of less than 1 s. Linear regression analysis of the abovementioned biosensors showed an excellent linear relationship. The proposed design provides a feasible solution for microwave biosensors aiming for the non-contact measurement of glucose concentration.
由于糖尿病患者数量的增加，对血糖水平的早期监测显得尤为重要；因此，葡萄糖生物传感器引起了研究人员的极大关注。本文提出了一种基于 RFID 的葡萄糖微波生物传感器，实现了对葡萄糖溶液浓度的非接触式测量。阅读器由互补开口环谐振器（CSRR）组成，标签由方形螺旋电容（SSC）组成。在标签上集成了一个体积为 1.56 μL 的聚二甲基硅氧烷微流定量腔，以确保葡萄糖溶液能够准确地设置在敏感区域并与电磁通量充分接触。由于 SSC 在接触不同浓度的葡萄糖溶液时表现出不同的电容，从而改变 CSRR 的谐振频率，我们可以利用这种关系来表征生物传感响应。测量结果表明，裸 CSRR 和基于 RFID 的生物传感器的灵敏度分别达到了 0.31 MHz/mg·dL 和 10.27 kHz/mg·dL，检测限分别达到了 13.79 mg/dL 和 1.19 mg/dL，并且都实现了小于 1 s 的响应时间。对上述生物传感器进行线性回归分析表明，它们具有优异的线性关系。该设计为非接触式测量葡萄糖浓度的微波生物传感器提供了一种可行的解决方案。
