title: Spectrophotometric method for high biomass concentration measurements.
abstract: Continuous monitoring of concentration is important in the optimal control of bioreactors. Spectrophotometry provides a simple, accurate, and rapid way for measuring cell concentration of unicellular microorganisms, based on either Beer's law or calibration curves prepared using standard solutions. However, this method is limited to a low range of microbial concentrations, because Beer's law deviates significantly at high concentrations. In the present investigation, based on experimental work, a new technique is posed to monitor the concentration of microbial cells as high as 100 g DW/L. this is achieved by using a mixture of known concentration as reference, rather than the "ideal blank" with zero concentration of analyte. As a result, a new equation is developed that, although applied here only to microbial concentration, in principle can be used for monitoring the concentration of any optically sensitive material.
authors.affiliation: Department of Chemical Engineering, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 0W0.
authors.forename: R
authors.initials: R
authors.lastname: Thatipamala
authors.forename: S
authors.initials: S
authors.lastname: Rohani
authors.forename: G A
authors.initials: GA
authors.lastname: Hill