Cavity coupled photonic crystal enhanced fluorescence for high sensitivity biomarker detection

photonic crystal;cavity coupled photonic crystal;mirror photonic crystal;silicon photonic crystal;biomarker detection;Fluorescence-linked immunosorbent assay (FLISA)

Foreman, Myles ; Cunningham ; Brian T.

关键词: photonic crystal;    cavity coupled photonic crystal;    mirror photonic crystal;    silicon photonic crystal;    biomarker detection;    Fluorescence-linked immunosorbent assay (FLISA);   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/90590/FOREMAN-THESIS-2016.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

With the rise in fluorescence-based testing of biomarkers in samples, the use of dielectric optical resonators has increased dramatically. These photonic crystals make fluorophores emit more light through a process called enhanced fluorescence which in turn allows for more signal to be collected due to these biomarkers. Advances in such optical resonators can lower limits of detection for the biomarkers or allow for cheaper and more practical tests to be performed for patients. This thesis looks at the theory and the engineering design process of these one-dimensional photonic crystals such that the mechanisms of enhanced fluorescence are increased themselves. It then introduces a new design concept of a photonic crystal with a mirror beneath. The mirror is expected to increase the quality factor of the guided mode optical resonator in the photonic crystal improving the mechanism of enhanced excitation acting on the fluorophore. The mirror is also expected to improve the mechanism of enhanced extraction by redirecting the emitted light from the fluorophore back to the detection instrumentation. The last fabrication steps are performed on the mirror photonic crystals to obtain experimental results. They are analyzed through simulated and experimental reflection spectra results to find that the enhanced excitation depends mainly on the quality factor of the guided mode resonator and the Fabry-Perot reflection dip envelope caused by constructive and destructive Fabry-Perot reflections. Enhanced extraction is also found to play an important role in the performance of the mirror photonic crystals through fluorescence-based tests using Alexa Fluor 647. Lastly, the mirror photonic crystals are put into a fluorescence-based test that uses silicon photonic crystals and attempts to find the E7 antibody in serum which is common in those who have HPV-related cancers.