基于空心双芯光纤的全光纤集成式光流控生物传感器

For the existing difficulties of the fiber optic biosensor to implement online testing, low sensitivity, and low level of integration, the project proposes a hollow core fiber-based all-fiber opticalflow control integrated fiber optic biosensor technology. On the basis of the proposed design of the hollow-core fiber microstructure with two cores, we realize the true meaning of "in-fiber" optofluidic biosensing for the samples through surface micromachining on the surface of the optical fiber, and improve the integration and stability of fiber optic biosensor. Also, we propose an interferometer integrated structure based on hollow-core optical fiber. By microfluidic sample injection, the fundamental mode of the core on the inner surface of the fiber can be affected by the microfluid. Then, the interference signal of the integrated fiber interferometer is modulated. Accurate information in biological samples can be obtained by measuring the change of the phase of the interference signal of the two core. The project proposed biosensor has the advantages of integrated all-fiber, high-sensitivity and low-cost. It provides a new optical flow control testing methods and techniques in the field of fiber optic biosensor. It has important scientific significance and application value for promoting the development of fiber-optic biosensor technology.

针对现有光纤生物传感器难于实现在线检测、灵敏度低、集成度低等问题，本项目提出了一种基于空心双芯光纤的全光纤集成式光流控生物传感技术。拟在设计空心双芯微结构光纤的基础上，通过光纤表面微加工实现真正意义的纤内（即“In-Fiber”）光流控生物样品检测，提高光纤生物传感器的集成度及稳定性。同时提出了基于空心双芯光纤的集成式光纤干涉仪结构，通过样品微流注入，使微流体影响光纤内表面芯基模的有效折射率，进而对纤维集成式干涉仪的干涉信号进行调制，通过测量两个纤芯干涉信号相位变化精确获取生物样品信息。本项目提出的生物传感器具有全光纤集成、灵敏度高、成本低的优点，为光纤生物传感领域提供一种全新的光流控检测方法和技术手段，对促进光纤生物传感技术的发展具有重要的科学意义和应用价值。

本项目针对目前光纤生物传感器的迫切需求，尤其是针对在线微流控、集成检测等领域的不足，设计并实现了基于空心双芯光纤的全光纤集成式光流控光纤生物传感结构。提出了基于空心双芯光纤的集成式光纤干涉仪结构。利用空心双芯微结构光纤及光纤表面微加工实现“In-fiber”光流控样品传感。通过微流注入光纤内部，并利用两个纤芯干涉信号相位变化获取生物样品信息，提高了光纤生物传感器的集成度及稳定性。具体完成了空心双芯光纤的结构、光耦合、实现了光纤表面开孔进样。对集成式光纤干涉仪进行了表征及各种相关的传感实验研究，主要包括：“In-fiber”干涉式光流控检测、基于空心双芯光纤的纤维集成式“In-fiber”气压传感器、双芯微结构光纤干涉式微流传感器在检测生物分子中的应用、基于悬挂芯空心光纤的光流控光纤内集成SERS检测等。本项目对促进集成式在线微流控光纤传感技术具有重要的科学意义和应用价值。