A thin-film pH sensor based on vibrational spectroscopy has been developed. The sensor was constructed by the immobilization of Congo Red at a base-hydrolyzed cellulose acetate film that had been coated onto a ZnSe internal reflection element. The protonation of the azo groups of Congo Red was monitored as a function of pH with infrared internal reflection spectroscopy. The response characteristics of this sensor demonstrate the potential utility of applying infrared spectroscopy to detect the response of thin film sensors. Opportunities to design sensors based on the molecular specificity of infrared spectroscopy are briefly discussed.
Thomas P. Jones and Marc D. Porter, "An Optical Sensor Based on Infrared Spectroscopy," Appl. Spectrosc. 43, 908-911 (1989)
References are not available for this paper.
OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.