基于有源内腔的复合镀膜式光纤SPR生物传感技术研究

Mainly aiming at the urgent requirements of label-free and real-time detection for micro-samples in biology and medicine areas, this project will carry out the research on the multi-layer coating type optical fiber SPR bio-sensing technique based on active intra-cavity structure. Based on the theoretical model of active intra-cavity optical fiber SPR sensor, the sensitivity enhancement mechanism for the optical fiber SPR sensing will be explored. And the influences of coating technology, multi-layer film structure and TFBG parameters on the sensitivity of the optical fiber SPR sensing will be discussed. The preparation technology of the optical fiber SPR immuno-sensor will be improved. Then an active intra-cavity structure based optical fiber SPR biological sensing system will be established. The demodulation algorithm for the biomolecule detection is studied, and the sensing experiments of biomolecule can be realized by using this system with a relatively higher sensitivity. This project will focus on the research of the sensitivity enhancement mechanism for the optical fiber SPR sensing. And the interaction mechanism between the optical fiber SPR sensor and the biomolecule will be also clarified further. Finally, the optical fiber SPR bio-sensing system will be established and optimized. And all these works will lay a strong foundation for the practical applications of this technology.

本项目主要针对生物医药行业对微量样品进行无标记、实时检测的迫切需求，开展基于有源内腔结构的复合镀膜式光纤SPR生物传感技术研究。在有源内腔光纤SPR传感理论模型的基础上，研究光纤SPR传感灵敏度增强机理，探索镀膜工艺、复合膜层结构以及倾斜光栅参数等对光纤SPR传感灵敏度的影响。完善光纤SPR生物传感器制备工艺，构建有源内腔光纤SPR生物传感系统，开发适用于生物分子检测的解调算法，实现生物分子高精度浓度传感。本项目拟着力探索光纤SPR传感灵敏度增强机理，进一步阐明传感器与生物分子耦合的微观机制，构建并完善光纤SPR生物传感系统，为其早日实现实用化奠定坚实基础。

用于生物大分子检测的传统方法（如ELISA、RIA等）大多操作复杂、需要标记、耗时长、样品耗费量大，而表面等离子体激元共振(surface plasmon resonance, SPR)传感检测则具有免于标记、实时检测、样品消耗量低等优点，成为生物化学领域的一个研究热点。基于光纤激光内腔吸收光谱学的气体传感技术具有响应速度快、光谱覆盖范围宽、光谱分辨率与检测灵敏度高等优点，非常适用于高精度的光纤生物传感领域。因此本项目将有源内腔技术和光纤SPR生物传感技术相结合，研究基于有源内腔结构的光纤SPR传感技术。 .通过本课题的研究，建立了完整的有源内腔的光纤SPR传感机理模型，给出了透射式SPR传感器的最佳物理参数。理论仿真并实验验证了二氧化钛薄膜厚度对于光纤表面等离子体谐振传感器工作光谱范围红移的影响程度及其对光纤表面等离子体谐振传感器折射率传感性能的影响。本项目提出了一种光纤SPR生物传感器的制作方法，研制了一批光纤SPR生物传感器，依次完成了兔免疫球蛋白抗原分子的增覆以及抗原抗体免疫性实验，实现了生物免疫实验的快速、高精度、无标记测量。