Biophotonics: Biophotonic Sensors Based on Polymer Microspheres Evanescently Coupled to Optical Fiber

[01:19273] arnold申请人拟研究基于介质微球与光纤瞬变耦合的光子传感器，并开发用于生化和生物传感的微球传感器。这种微球中前所未有的窄光共振为新型全光传感器开辟了道路，这种传感器可以通过检测共振的光频移来测量局部特性。在极窄线宽的微球中，出现了许多光子共振模式。通过扫描通过光纤传输到微球的激光的波长，并通过与微球耦合的读出光纤观察其强度，从而获得共振谱。共振波长位移对球体直径和折射率的变化以及球体周围介质折射率的变化极为敏感。后一种量是由温度、第二种物质在球体表面的吸附、各向同性和各向异性应力以及球体周围溶液中化学物质的浓度决定的。将特别致力于开发用于生物流体的微观传感头。为此目的，将使用纤维和微球，它们都是由具有生物相容性的聚合物制成的。生物分子相互作用的高特异性将使检测特定的RNA，蛋白质，酶，底物和抗原成为可能。其目标是使人们能够制备与生物分子数量一样多的传感器。微型，高灵敏度的生物光子传感器的可用性将促进“芯片上的设备”和其他并行化学和生物分析系统在组合化学中的发展。

0119273ArnoldThe applicant proposes to investigate photonic sensors based on dielectric microspheres evanescently coupled to optical fibers, and to develop microsphere sensors for biochemical and biological sensing. The unprecedentedly narrow optical resonances in such microspheres open an avenue for a novel class of all-optical sensors which can measure local properties by detecting optical frequency shifts of the resonances. Many photonic resonance modes occur in a microsphere in an extremely narrow linewidth. The resonance spectrum is obtained by scanning the wavelength of the laser transmitted through the fiber into the microsphere and observing the intensity through a read-out fiber coupled to the microsphere. Resonance wavelength shifts are extremely sensitive to changes in the diameter and the refractive index of the sphere as well as the refractive index of the medium surrounding the sphere. The latter quantities are determined by the temperature, adsorption of a second substance onto the sphere surface, the isotropic and anisotropic stress, and the concentration of a chemical in the solution surrounding the sphere. Efforts will be especially targeted at developing microscopic sensing heads for biofluids. For this purpose fibers and microspheres, all made of polymers that can be rendered biocompatible will be used. The high specificity in biomolecular interactions will enable detection of a specific RNA, protein, enzyme, substrate, and antigen. The goal is to allow one to prepare as many kinds of sensors as the number of biomolecules. Availability of miniature, high-sensitivity biophotonic sensors will facilitate the development of 'device on a chip' and other parallel chemical and biological analysis systems in combinatorial chemistry.