Advanced three-dimensional lab-on-a-chip architectures for integrated surface-enhanced Raman spectroscopy (LoC-SERS)

芯片实验室表面增强拉曼光谱（Sers）是一种非常有前途的低浓度水中分析物的灵敏生化检测方法。然而，有两个问题需要解决。首先，低成本的芯片上集成的Sers纳米结构的增强因子的高再现性的制造仍然是空缺的。第二，芯片上集成的激光激发源，特别是光谱可调谐激光源，对于该应用仍然缺失。这项建议提出了一个跨学科的方法，结合微/纳米系统工程和纳米光子学的表面增强拉曼光谱应用。该项目的主要目标是在技术上实现集成有机半导体激光器的拉曼芯片光流体平台。此外，我们的目标是一个基本的理解和优化的局部表面等离子体共振（LSPR）的Sers应用，使用低成本的金属有机混合纳米结构阵列。我们的工作将主要针对以下几个问题：（1）利用激光辅助热压成型技术，将周期性的纳米粒子压印到聚合物基底上。金属-有机杂化纳米图案的拉曼增强因子将在非集成Sers基底上进行实验表征。2.）的情况。将使用时域有限差分（FDTD）建模模拟研究各种几何形状的周期性纳米粒子，旨在提高在不同激发波长下的Sers增强因子，用于生化分析。将与实验工作保持密切的反馈循环。3.）第三章优化的纳米粒子将被集成到聚合物芯片上的微流体通道中。作为进一步的集成步骤，有机半导体分布反馈（DFB）激光器将被引入到芯片上使用激光辅助复制和喷墨打印的组合。Sers芯片将完成后，封装与聚合物盖，这将是通过激光传输焊接实现。4.）使用有机DFB激光器的Sers激发将以第一种方式通过引入外部光学元件来实现，市售的离轴抛物面镜。在第二种方式中，包括集成光学部件的功能性聚合物盖将在SERS分析场上实现垂直激光激发。集成反射镜的几何形状和公差将使用系统的光学设计进行研究。封装工艺采用激光透射焊接，定位精度高。5.）最后，我们将根据我们制造的SERS纳米粒子和LOC-SERS芯片进行第一次生化测试。因此，我们的目标是展示现场在线水质监测，以及肽致癌基因中癌症特异性突变的生物医学诊断。

Lab-on-a-chip surface-enhanced Raman spectroscopy (SERS) is a very promising method for sensitive biochemical detection of low-concentrated analyte in water. However, two issues should be addressed. First, low-cost fabrication of on-chip-integrated SERS nanostructures with high reproducibility in enhancement factor is still vacant. Second, an on-chip-integrated laser excitation source, especially a spectrally tunable laser source, is still missing for this application. This proposal suggests an interdisciplinary approach, combining micro-/nano-systems engineering and nanophotonics for surface-enhanced Raman spectroscopy applications. The main objective of the project is the technical realization of a Raman-on-chip optofluidic platform with integrated organic semiconductor lasers. Furthermore we aim at a fundamental understanding and an optimization of localized surface plasmon resonances (LSPR) for SERS applications using low-cost metal-organic hybrid nanostructure arrays. Our work will mainly address the following issues: 1.) Using laser-assisted hot embossing, the process for defining periodic nanopatterns into polymeric substrate will be explored. The Raman enhancement factor of metal-organic hybrid nano-patterns will be experimentally characterized on non-integrated SERS substrates. 2.) Periodic nanopatterns in various geometries will be investigated using finite-difference-time-domain (FDTD) modeling simulations, aiming to improve the SERS enhancement factor at different excitation wavelengths for biochemical analysis. A close feedback loop with the experimental work will be maintained. 3.) The optimized nanopatterns will be integrated into the microfluidic channels on a polymeric chip. As a further step of integration, organic semiconductor distributed feedback (DFB) lasers will be introduced onto the chip using a combination of laser-assisted replication and ink-jet printing. The SERS chip will be finalized after the encapsulation with a polymeric lid, which will be achieved by laser transmission welding. 4.) SERS excitation using an organic DFB laser will be realized in the first way by introducing external optical elements, e.g., commercial available off-axis parabolic mirrors. In the second way, a functional polymeric lid which comprises integrated optical components is to achieve a perpendicular laser excitation on SERS-analysis fields. The geometry and tolerance of integrated mirrors will be investigated using systematic optics design. The encapsulation process will be achieved by laser transmission welding with high precision in positioning. 5.) Finally we will perform first biochemical tests based our fabricated SERS-nanopatterns and LOC-SERS chips. Therefore we aim at demonstrating on-site inline water quality monitoring and moreover biomedical diagnostics of cancer-specific mutations in the oncogene of the peptide.