Thesis presented March 26, 2021

Abstract:
Surface Plasmon Resonance Imaging is a technique widely used in the field of biomolecular sensing in the liquid phase. In 2012, our laboratory demonstrated its applicability as an optoelectronic nose using a peptide-based sensor array. Soon after, a functional device was valorized by the start-up Aryballe Technologies towards the sensitive and selective detection of Volatile Organic Compounds (VOCs) in the gas phase. Since its conception, a fundamental understanding regarding its plasmonic sensitivity and recognition mechanisms, in the context of gas-phase detection and discrimination, has not been performed. This Ph.D. thesis attempts to unravel these underlying mechanisms governing the functionality of the device. Firstly, the plasmonic contribution mechanism in the gas phase was investigated and elucidated through the elaboration of a comprehensive numerical model based on the Transfer Matrix Formalism. A corrective approach was proposed to adapt this model to better represent experimental realities in light of a surface topography associated mismatch. Secondly, the biomolecular receptor contributions were studied, from peptide immobilization to their interaction mechanisms with small VOCs in the gas phase. Moreover, a particular emphasis was devoted to studying the temperature and humidity effects. Finally, the use of a specially designed surfactant-like peptide was proposed towards the fabrication of bio-hybrid surface nanoarchitecture, through which a functional sensor array was developed with sensing elements solely varying in surface morphology. In essence, the interplay between structure and function has been the overarching theme of this work, potentially paving the way towards achieving higher performances for such optoelectronic nose devices.

Keywords:
Surface Plasmon Resonance Imaging, Optoelectronic Nose, Peptides, Volatile Organic Compounds, Self-assembly, Temperature and Humidity