基于光栅波导共振耦合的传感器特性研究

Research of Biosensor Characteristics Based on Grating Waveguide Coupling Resonance Angle

该文设计了一种基于光栅波导共振角耦合的生物传感器,通过光栅波导模式谱变化检测传感器表面有效折射率变化的方式,实现了传感器表面附着物的精确检测。并在平板介质光波导理论基础上,推导了三、四层结构理论模型,实验得到了入射角与检测溶液折射率及入射角与分子膜层厚度间的变化关系。结果表明,光栅波导共振角耦合生物传感器入射角与待测溶液折射率存在良好的线性关系,并具有较高灵敏度,精度可达0.01(°)/nm。通过该方法制作出无标记的生物传感器,能广泛应用于生物分子检测,尤其适合蛋白质分子生物检测。

A biosensor based on grating waveguide coupling resonance angle has been designed.It achieves accurate detection for adsorbate on sensor surface through the change of grating waveguide mode spectrum to detect the change of optical refractive index on the sensor surface.The theoretical models of the three-layer structure and fourlayer structure have been derived on the basis of the plate medium optical waveguide theory.The relationships among the incident angle and the refractive index of the detected solution and the molecular membrane layer thickness have been drawn through the experiment.The results show that there is a good linear relationship between the incident angle and the refractive index of the solution to be measured,and the sensor has high sensitivity of 0.01（°）/nm.The proposed method can be used to fabricate the label-free biosensor for the biological molecule diction,particularly for protein molecular biological diction.