CAREER: Fluorescence Resonant Energy Transfer in Opto-fluidic Ring Resonators for Ultrasensitive Biomolecule Detection

光流体环形谐振器（OFRR）是一种光子技术，最初发明于PI的实验室。OFRR将极高Q值（107）的光学腔与微流体技术相结合，实现了高效的样品输送和通过流体的光控制。由于这些新颖的特性，OFRR在生物/化学传感器、光子器件和基础物理等领域有着广泛的应用。特别是在拟议的研究中，PI将OFRR研究扩展到荧光共振能量转移（FRET）。FRET已广泛应用于生物和化学传感器。然而，超过福斯特距离（2-10 nm）的极低能量转移效率严重恶化了FRET传感能力，特别是对于大的生物分子。PI的最近的研究，沿着与其他小组进行的早期，已经表明，FRET效率可以大大提高通过远程腔辅助能量转移和非线性激光作用的光学腔。这些特性可以用来克服传统FRET生物传感的局限性。该研究的总体目标是对OFRR中的FRET过程进行基础研究，并利用强大的OFRR和FRET技术开发一种新型的小型化和高灵敏度的光子生物传感系统，甚至可以在单分子水平上操作。

Opto-fluidic ring resonator (OFRR) is a photonic technology originally invented in the PI's lab. The OFRR integrates the optical cavity of extremely high Q-factors (107) with microfluidics, enabling efficient sample delivery and control of light through fluids. Because of these novel characteristics, the OFRR has broad applications in many fields, including bio/chemical sensors, photonic devices, and fundamental physics. In the proposed research, in particular, the PI wilo expand the OFRR study into fluorescence resonant energy transfer (FRET). FRET has been extensively employed in biological and chemical sensors. However, extremely low energy transfer efficiency beyond the Forster distance (2-10 nm) has severely deteriorated the FRET sensing capability, especially for large biomolecules. The PI's recent studies, along with those conducted earlier by other groups, have shown that FRET efficiency can be drastically enhanced by an optical cavity through long-range cavity assisted energy transfer and nonlinear lasing action. These properties can be exploited to overcome the limitations of the traditional FRET-based biosensing. The overall aim of the proposed research is to conduct a fundamental investigation into FRET processes in the OFRR and to harness the powerful OFRR and FRET technologiesto develop a novel miniaturized and highly sensitive photonic biosensing system that can be operated at even the single molecule level.