This is a whole new area with essentially uncharted territory for the biochemical engineering profession with great potential for widespread and lasting impact. Non-Invasive Sensors Recent developments in the fields of spectroscopy have afforded engineers the opportunity to use fluorescence in bioreactors to obtain online information on cellular reduction states. Much work needs to be done with a variety of culture systems to develop the database necessary for the measurement and interpretation of culture fluorescence spectra before these techniques can be widely adapted for bioreactor monitoring and control. Development of such non-invasive sensors is also important from the point of view of bioenergetic parameter estimations. Another non-invasive sensor that is easy to use and that gives a measure of the extracellular reduction state is redox potential.
Work is in progress to explore the relationship between extra- and intracellular reduction states.
Recently, we have begun to explore a new class of fluorescence lifetime based sensors for oxygen, pH, CO2 and glucose for bioprocess and biomedical applications. Hyperoxia Induces DNA Damage in Mammalian Cells. Simon C. W. Kwong, Lisa Randers and Govind Rao. Steve Altman, Lisa Randers and Govind Rao. 1993. Simon C. W. Kwong and Govind Rao.