1 September 1991 Fiber optic fluorescence sensors based on sol-gel entrapped dyes
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Proceedings Volume 1510, Chemical and Medical Sensors; (1991) https://doi.org/10.1117/12.47129
Event: ECO4 (The Hague '91), 1991, The Hague, Netherlands
Many fiber optic sensors for chemical species rely on a change in the fluorescence characteristics of a dye in response to its chemical environment. Such sensors often require the complex immobilization of the fluorescent species on or near the fiber surface. A novel process, whereby a highly transparent porous glass can act as a support for sensor dyes, is presented. The sol-gel process for low-temperature fabrication of porous glass has been used as a means of entrapping chemically-sensitive dyes for fiber optic sensor applications. As a proof of principle, fluorescein dye was used to investigate the performance of a pH sensor. Because of its potential for distributed sensing and planar integrated optics sensors, evanescent-wave rather than direct excitation of fluorescence was used. A short length of unclad fiber was coated with a thin layer of porous cladding within which the pH-sensitive dye is entrapped. The sensor displayed maximum sensitivity in the range of pH 3.5 to pH 6.5 with a response time of less than 5 seconds. The suitability of the technique for distributed and integrated-optic sensing of gaseous and liquid species is discussed.
© (1991) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Brian D. MacCraith, Brian D. MacCraith, Vincent P. Ruddy, Vincent P. Ruddy, C. Potter, C. Potter, John F. McGilp, John F. McGilp, Brendan O'Kelly, Brendan O'Kelly, } "Fiber optic fluorescence sensors based on sol-gel entrapped dyes", Proc. SPIE 1510, Chemical and Medical Sensors, (1 September 1991); doi: 10.1117/12.47129; https://doi.org/10.1117/12.47129


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