The application of fluorescence spectroscopy for biosensing applications

• Main Author: O'Neal, Dennis Patrick Doucet
• Format: Dissertation
• Language: English
• Subjects: engineering, biomedical
• ISBN: 0493467750; 9780493467757

Fluorescence spectroscopy as employed for biomedical sensing has the promise to replace many non-optical sensing systems currently in use. The goal in developing these fluorescence-based systems is to make biosensors that are less invasive, equally or more robust, and less expensive than existing technologies. This dissertation examines the development of fluorescence-based biomedical optics instrumentation and data analysis techniques for the quantification of systemic glucose levels in mammals and oxygen levels in long-term cell culture experiments. The relationship between these two very different applications is that similar chemical techniques can be used in both that employ a variety of fluorescent compounds immobilized in water-soluble biocompatible polymers. Fluorescence data and/or spectra were obtained using either visible laser or light emitting diode (LED) sources. The detector used was either a charge-coupled device (CCD) sensing array or a point detector such as a photo-multiplier tubes (PMT) or a silicon photo-diode. The oxygen sensing project required that polymer slabs be investigated in vitro for various oxygen levels in solution and compared to a commercial probe. Development of a glucose sensitive sensing system required that several different fluorophores determined to be good candidates for resonance energy transfer (RET) were evaluated with respect to glucose sensitivity and compared to the traditional fluorscein isothiocyanate (FITC) dextran/tetramethylrhodamine isothiocyanate (TRITC) concanavalin A (ConA) system. Lastly, the ability of these signals to be collected through skin with point detectors and CCD arrays was compared using linear statistical modeling and multivariate calibration.