Department of Mechanical Engineering, Advanced Institute of Manufacturing with High-Tech Innovations (AIM-HI), National Chung Cheng University, Minxiong Township 62102, Taiwan.
Biosensors (Basel). 2021 Dec 20;11(12):523. doi: 10.3390/bios11120523.
The rapid and sensitive detection of human C-reactive protein (CRP) in a point-of-care (POC) may be conducive to the early diagnosis of various diseases. Biosensors have emerged as a new technology for rapid and accurate detection of CRP for POC applications. Here, we propose a rapid and highly stable guided-mode resonance (GMR) optofluidic biosensing system based on intensity detection with self-compensation, which substantially reduces the instability caused by environmental factors for a long detection time. In addition, a low-cost LED serving as the light source and a photodetector are used for intensity detection and real-time biosensing, and the system compactness facilitates POC applications. Self-compensation relies on a polarizing beam splitter to separate the transverse-magnetic-polarized light and transverse-electric-polarized light from the light source. The transverse-electric-polarized light is used as a background signal for compensating noise, while the transverse-magnetic-polarized light is used as the light source for the GMR biosensor. After compensation, noise is drastically reduced, and both the stability and performance of the system are enhanced over a long period. Refractive index experiments revealed a resolution improvement by 181% when using the proposed system with compensation. In addition, the system was successfully applied to CRP detection, and an outstanding limit of detection of 1.95 × 10 g/mL was achieved, validating the proposed measurement system for biochemical reaction detection. The proposed GMR biosensing sensing system can provide a low-cost, compact, rapid, sensitive, and highly stable solution for a variety of point-of-care applications.
在即时检测（POC）中快速灵敏地检测人 C 反应蛋白（CRP）可能有助于各种疾病的早期诊断。生物传感器作为一种用于 POC 应用的快速准确检测 CRP 的新技术已经出现。在这里，我们提出了一种基于强度检测和自补偿的快速、高稳定性导模共振（GMR）光流控生物传感系统，该系统大大减少了由于环境因素引起的长时间检测的不稳定性。此外，我们还使用了低成本的 LED 作为光源和光电探测器进行强度检测和实时生物传感，系统的紧凑性便于在 POC 中应用。自补偿依赖于偏振分光镜将光源的横磁偏振光和横电偏振光分离。横电偏振光用作补偿噪声的背景信号，而横磁偏振光则用作 GMR 生物传感器的光源。补偿后，噪声大大降低，系统的稳定性和性能在长时间内都得到了提高。折射率实验表明，使用带有补偿的建议系统可以将分辨率提高 181%。此外，该系统成功应用于 CRP 检测，实现了 1.95×10 g/mL 的出色检测限，验证了该测量系统在生化反应检测中的应用。所提出的 GMR 生物传感系统可以为各种即时护理应用提供一种低成本、紧凑、快速、灵敏和高稳定性的解决方案。
