Changes in heat content are almost universally associated with chemical reactions. Thermometry as an analytical tool has been extensively researched and developed. Finding solutions to problems involving thermal isolation, specificity, sensitivity, and cross-sensitivity remain as active areas of interest. Fiberoptic interferometers, which use phase phenomena associated with propagating light, are extremely sensitive to heat. This research has focused on a special "birefringent" optical fiber. Two channels of information are generated in this single-fiber interferometer which correspond to the heat evolved from a catalytic reaction isolated on the fiber surface. Because of the unique transduction mechanism associated with the "birefringent" optical fiber, this device is sensitive to heat and remarkably insensitive to pressure. Details of the characterization and development of the birefringent optical fiber into a useful analytical probe are presented. / Ph. D.