Zhang Yu-Jun, Hsu Jin-Cherng, Tsao Jia-Huey, Sun Yung-Shin
Department of Physics, Fu-Jen Catholic University, New Taipei City 24205, Taiwan.
Industrial Technology Research Institute, Hsinchu 31040, Taiwan.
Micromachines (Basel). 2019 Aug 8;10(8):522. doi: 10.3390/mi10080522.
A bare optical fiber-based biosensor is proposed for measuring the refractive index of different liquids and the binding kinetics of biomolecules to the sensor surface. This optical fiber sensor is based on the Kretschmann's configuration to attain total internal reflection (TIR) for surface plasmon resonance (SPR) excitation. One end of the bare optical fiber is coated with a gold film. By guiding the light source from the other end into the optical fiber, the light is reflected from the gold-deposited end and the surface evanescent wave is excited in the gold film-transparent material interface. Methanol and ethanol solutions with different refractive indices are used for measuring the corresponding changes in the peak values of the spectra and calculating the corresponding sensitivities. These values are experimentally determined to be in the order of 10~10 refractive index unit (RIU). Binding of proteins onto the sensor surface is also monitored in real time to obtain the binding kinetics. We believe that, in the future, this optical fiber sensor can serve as a useful biosensor for in situ measurement of allergens, antibody-antigen interactions, and even circulating tumor cells in the blood.
提出了一种基于裸光纤的生物传感器，用于测量不同液体的折射率以及生物分子与传感器表面的结合动力学。这种光纤传感器基于克雷奇曼配置，以实现用于表面等离子体共振（SPR）激发的全内反射（TIR）。裸光纤的一端涂有金膜。通过将光源从另一端导入光纤，光从涂有金的一端反射，并且在金膜 - 透明材料界面中激发表面倏逝波。使用具有不同折射率的甲醇和乙醇溶液来测量光谱峰值的相应变化并计算相应的灵敏度。通过实验确定这些值在10~10折射率单位（RIU）的量级。还实时监测蛋白质在传感器表面的结合以获得结合动力学。我们相信，在未来，这种光纤传感器可以作为一种有用的生物传感器，用于原位测量过敏原、抗体 - 抗原相互作用，甚至血液中的循环肿瘤细胞。
