Tunable Micro-Optofluidic Ring Resonator Arrays as Micro Gas Chromatograph Detectors

本研究的目的是开发具有前所未有的识别不同挥发性有机化合物能力的纳米包覆微制造光流控环形谐振器传感器阵列，将这种阵列用作气相色谱微系统中的检测器，并展示对任意复杂混合物中目标化合物的定量分析。这种方法需要微加工具有波限制轮廓的高纵横比谐振器，通过使用包含硫代单层保护的金纳米颗粒的蒸汽吸附界面层来展示增强的蒸汽识别，并将这种微谐振器阵列集成到微系统中。这项研究带来了一种新的蒸汽传感器阵列设计方法，这将导致第一个使用可扩展的精密微制造技术制造的微细加工光流控环形谐振器探测器。所提出的器件结构固有地保证了更高的蒸气灵敏度。由于水蒸气引起的折射率变化将随着纳米颗粒尺寸、硫酸盐配体功能和探测波长的不同而不同，这类设备的阵列承诺比当前传感器阵列产生的响应多样性更大，这将增强对水蒸气的识别。广泛影响成功的项目将满足对小型、廉价、交钥匙仪器的需求，用于测定复杂混合物中痕量水平的多种水蒸气，并直接应用于疾病生物标志物、爆炸物和空气传播有毒物质的检测。通过现有的调查人员关系，将项目成果传播给世界各地以技术为导向的公司和领先的微系统研究中心的代表将得到便利。这将促进已开发技术的商业化，并扩大向学生提供的关于该项目的培训范围。

The objective of this research is to develop arrays of nanoparticle-coated microfabricated opto-fluidic ring resonator sensors with unprecedented capabilities to discriminate among different volatile organic compounds, to use such an array as the detector in a gas chromatographic microsystem, and to demonstrate the quantitative analysis of targeted compounds in arbitrarily complex mixtures. The approach entails micromachining high-aspect-ratio resonators with wave confinement contours, demonstrating enhanced vapor discrimination by use of vapor-sorptive interface layers comprising thiolate-monolayer-protected gold nanoparticles, and integrating arrays of such micro-resonators into the microsystem.Intellectual Merit This research entails a new approach to vapor sensor array design, which will lead to the first microfabricated optofluidic ring resonator detectors made using scalable, precision microfabrication techniques. The proposed device structures promise inherently greater vapor sensitivity. Since vapor induced changes in refractive index will vary with the nanoparticle size, thiolate-ligand functionality, and probing wavelength, arrays of such devices promise response diversity inherently greater than that produced by current sensor arrays, which will enhance vapor discrimination.Broader ImpactsThe successful project will fill a need for small, inexpensive, turn-key instrumentation for the determination of multiple vapors at trace levels in complex mixtures, with direct application to the detection of disease biomarkers, explosives, and airborne toxicants. Dissemination of project results to representatives of technology-oriented companies and leading microsystem research centers throughout the world will be facilitated through extant affiliations of the investigators. This will promote the commercialization of the developed technologies and expand the scope of training provided to the students on the project.