Cai Haoyuan, Shan Shihan, Wang Xiaoping
Ocean College, Zhejiang University, Zhoushan 316021, China.
Key Laboratory of Ocean Observation-Imaging Testbed of Zhejiang Province, Zhejiang University, Zhoushan 316021, China.
Nanomaterials (Basel). 2021 Dec 15;11(12):3399. doi: 10.3390/nano11123399.
Surface plasmon resonance (SPR) biosensors consisting of alternate layers of silver (Ag) and TiO thin film have been proposed as a high sensitivity biosensor. The structure not only prevents the Ag film from oxidation, but also enhances the field inside the structure, thereby improving the performance of the sensor. Genetic algorithm (GA) was used to optimize the proposed structure and its maximum angular sensitivity was 384°/RIU (refractive index unit) at the refractive index environment of 1.3425, which is about 3.12 times that of the conventional Ag-based biosensor. A detailed discussion, based on the finite difference time domain (FDTD) method, revealed that an enhanced evanescent field at the top layer-analyte region results in the ultra-sensitivity characteristic. We expect that the proposed structure can be a suitable biosensor for chemical detection, clinical diagnostics, and biological examination.
由银（Ag）和TiO薄膜交替层组成的表面等离子体共振（SPR）生物传感器已被提出作为一种高灵敏度生物传感器。该结构不仅可防止Ag膜氧化，还能增强结构内部的场，从而提高传感器的性能。遗传算法（GA）用于优化所提出的结构，在折射率为1.3425的环境中其最大角度灵敏度为384°/RIU（折射率单位），约为传统基于Ag的生物传感器的3.12倍。基于时域有限差分（FDTD）方法的详细讨论表明，顶层 - 分析物区域处增强的倏逝场导致了超灵敏特性。我们期望所提出的结构能够成为适用于化学检测、临床诊断和生物学检测的生物传感器。
