Advancements in optics-based chemical and biosensors with array applications

Chemical- and biosensor research and development has seen a surge in the last two decades. This work covers the development of new optics-based sensor systems employing surface plasmon resonance (SPR) and frequency-domain lifetime fluorimetry transduction techniques.; We address the issue of optimizing sensitivity through choice of excitation wavelength in prism-based SPR sensor systems. We provide experimental data illustrating the benefits of using yellow (594.1 nm) laser light with gold films in SPR sensor systems.; One of the serious issues with SPR sensor measurements is their (unwanted) sensitivity to changes in temperature and solute concentration. We present a new and simple method for compensating for both of these phenomenon with a single, inert reference element in a sensor array.; Fiber-optic SPR sensor systems have traditionally been difficult to work with, due to instabilities or lack of sensitivity in aqueous environments. We present a single-mode fiber based SPR biosensor (in aqueous environments), using 594.1 nm excitation light. We offer a model for the interactions of a fiber Bragg grating with the plasmon resonance, and provide experimental data obtained using such a system.; We show a new SPR sensor array platform based on spectroscopic imaging. Our approach crosses one-dimensional microscopy with “fan-type” SPR spectroscopy. We provide several experimental demonstrations of its suitability for biosensor measurements.; We present a new frequency-domain fluorescence lifetime sensor technique based on an optoelectronic, closed-loop system. The frequency of self-oscillations in this system changes as fluorescence lifetime changes, and is used as the sensing parameter. This new technique offers high sensitivity at low cost.; Finally, we discuss a unique, 16 channel, fluorescence-lifetime based sensor array platform. This inexpensive system uses single-frequency modulation spectroscopy to monitor the changes in a excited-state lifetimes. We provide several experimental demonstrations of this unit's capability of performing measurements with fluorescence-based sensor arrays.