Abstract
We have developed a fiber-optic chemical sensor for on-line monitoring of fermentation pH. The sensor is based on a covalently bound fluorescent dye immobilized within a water-permeable polymer layer on an optical fiber. Measurements were performed on a portable fluorimeter and employed a ratiometric approach to account for system instabilities. We show that the use of this fiber-optic sensor provides fast, accurate and reliable measurements during E. coli fermentation in a complex medium.
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Agayn, V., Walt, D. Fiber-optic Sensor for Continuous Monitoring of Fermentation pH. Nat Biotechnol 11, 726–729 (1993). https://doi.org/10.1038/nbt0693-726
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DOI: https://doi.org/10.1038/nbt0693-726