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

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

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 Impacts The 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.