Sensing Using Fluorescent-Core Microcapillaries

• Author / Creator

  Lane, Stephen A

• This thesis covers microfluidic sensing using whispering gallery modes supportedin silica microcapillaries coated with a fluorescent film, hereby calledfluorescent core microcapillaries (FCMs). We give an introduction to this classof device, and describe how it can be built and used effectively in microfluidicsensing. We then discuss the theory and experimental observations of thesemodes, including their shape, origin, wavelength, efficiency, and refractometricsensitivity. The thickness of the fluorescent film is a key factor in optimizingFCM-based detection, as is the polarization and order of the mode analyzed.Next, the effect of thermal fluctuations within a WGM is discussed. Filmthickness, film composition, and analyte solvent play key roles in the thermalresponse of this device, and complete thermal stability is theoretically shownand approximately demonstrated. We developed a method for functionalizationof the channel surface using a polyelectrolyte strategy, and subsequentlydemonstrate nanomolar detection of neutravidin. We conclude with a discussionof outstanding obstacles and potential avenues for further research. Theappendix contains initial research on an organic lasing chromophore that maybe a future component of the fluorescent film.

• Subjects / Keywords

  • fluorescence
  • resonance
  • whispering
  • physics
  • sensing
  • gallery
  • fluorescent-core
  • microcapillary
  • microfluidic
  • quantum dot
  • microresonator
  • fluorescent
  • lasing
  • WGM
  • detection
  • mode
  • whispering gallery mode
  • chromophore
  • microcapillaries
  • biosensing

• Graduation date

  Spring 2019

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/r3-fed7-d972

• License

  Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.