A sensor, a method for its fabrication, and a method for its use to detect contaminants, for example, ammonia, in stagnant and dynamic fluid media, especially liquid media. The sensor is an opto-chemical sensor that includes a polymer optical fiber, a sensing layer comprising oxazine 170 perchlorate on the polymer optical fiber, and a membrane layer on the sensing layer. The membrane layer is gas permeable and not permeable to the fluid in the fluid system, and moisture is entrapped by and between the sensing and membrane layers.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
This invention was made with government support under Contract No. DE-FG02-05ER64131 awarded by the U.S. Department of Energy. The Government has certain rights in the invention.