Resonant-Photonic-Device-Enhanced SERS Substrate with Pinpointed Plasmonic-Active

描述（由申请人提供）：由于制造超灵敏和可再现的表面等离子体共振（SPR）基底的巨大困难，表面增强拉曼散射（Sers）用于生物分子检测的使用受到限制。因此，用于临床应用的检测极少量的生物分子是显著受限的。 在这个STTR第二阶段的研究中，我们建议开发超灵敏（1012~1014增强因子）的Sers基板与普遍可用的拉曼“热点”，以及可重复的生物分子检测相结合的光场增强共振光子器件和金属纳米实体。与现有的SPR基板通过旋涂胶体纳米粒子或纳米线溶液，我们工程的Sers基板使用二氧化硅纳米管涂有普遍分布的银纳米粒子，这可以显着增加的拉曼散射“热点”的密度。我们还采用了高鲁棒性的Si 3 N4导模共振（GMR）光栅和共振微腔阵列，以实现更高的局部电场Sers传感。为了将这两项创新联系起来，我们将应用一种非常精致的工具-电镊子，将SPR活性纳米管组装成具有无与伦比的空间精度至少为150 nm的共振光子器件。在我们的第一阶段计划中，我们从理论上模拟并实验证明了具有纳米尺寸间隙的SPR活性二氧化硅纳米管，并检测到低至100 fM（单分子水平）的罗丹明6 G，增强因子为1.1x1010。此外，我们制作的Si 3 N4 GMR光栅使用国家的最先进的纳米纤维工艺和实验上实现了~10？增强因子除了来自SPR活性二氧化硅纳米管的现有Sers效应之外。在二期计划中，我们将继续优化Sers基底，使SERS灵敏度达到1012~1014增强因子，提高真实的生物样品中超低浓度生物分子的检测概率，并将Sers基底应用于各种生物医学应用。最重要的是，我们将解决产品商业化的潜在技术挑战，包括降低制造成本，提高产量，用光纤系统封装Sers衬底和评估器件可靠性。

DESCRIPTION (provided by applicant): The use of Surface Enhanced Raman Scattering (SERS) for biomolecule detection has been restricted due to the great difficulty of fabricating ultrasensitive and reproducible surface-plasmonic-resonance (SPR) substrates. Therefore, detecting extremely small amount of biomolecules for clinical application is significantly limited. In this STTR Phase II research, we propose to develop ultrasensitive (1012~1014 enhancement factors) SERS substrates with universally available Raman "hot spots" for well-reproducible biomolecule detection by combining optical field enhancements from both resonant photonic devices and metallic nanoentities. Compared with existing SPR substrates made by spin-coating colloidal nanoparticles or nanowire solutions, we engineer the SERS substrate using silica nanotubes coated with universally distributed silver nanoparticles, which can dramatically increase the density of the Raman scattering "hot spots". We also employ highly robust Si3N4 guided-mode-resonance (GMR) gratings and resonant microcavity array to achieve even higher local electric field for SERS sensing. To link these two innovations, we will apply a highly exquisite tool---electric tweezers, to assemble the SPR-active nanotubes into the resonant photonic devices with unbeatable spatial precision of at least 150 nm. In our Phase I program, we have theoretically simulated and experimentally demonstrated SPR-active silica nanotubes with nanometer-size gaps, and detected Rhodamine 6G down to 100 fM (single-molecule level) with enhancement factors of 1.1x1010. Moreover, we fabricated Si3N4 GMR gratings using state-of-the-art nanofabrication processes and experimentally achieved ~10? enhancement factors in addition to the existing SERS effect from the SPR-active silica nanotubes. In the Phase II program, we will continue to optimize the SERS substrates for ultrahigh sensitivity up to 1012~1014 enhancement factors, improve the detection probability of ultralow concentration biomolecules in real biological samples, and apply the SERS substrates in various biomedical applications. Most of all, we will resolve potential technical challenges for product commercialization, including lowering the fabrication cost, increasing the throughput, packaging the SERS substrate with fiber-optic systems and evaluating the device reliability.