Plasmonic Sensor using Double-layered Stimuli-responsive Polymer Microgel for Multiplexed Detection
[Thesis]
Mundel, Hannah Beverly Elizabeth
Aitchison, James Stewart
University of Toronto (Canada)
2019
110
M.A.S.
University of Toronto (Canada)
2019
Herein we present a sensor that uses surface plasmon resonance (SPR) and plasmonic waveguide resonance (PWR) modes to probe the behavior of two layers of stimuli-responsive polymers, called microgels, deposited on a gold film. These microgels can be molecularly imprinted, resulting in a high-loading-capacity synthetic receptor. In response to external stimuli, such as molecular binding events, their refractive index and thickness vary. Fabrication and testing demonstrated that changes in the SPR mode correspond to changes in the lower layer's refractive index and thickness with p-values below 0.03, whereas changes in the PWR mode correspond to changes in the upper layer's refractive index and thickness with p-values<0.02. The corresponding lowest limits of detection are 0.00073 RIU and 11 nm, and 0.0024 RIU and 41 nm, respectively. Furthermore, simulations indicate that good sensitivity to each layer is achievable, and that signal decoupling can be improved using TE PWR modes and Fabry-Perot resonances.