RAPID-DETERMINATION OF TOTAL BIOMASS FROM A YEAST FERMENTATION USING SEQUENTIAL INJECTION

An assay for the measurement of the total biomass in an unfiltered fer mentation sample has been developed using a simple sequential injectio n system, with either total transmitted light or light scattered at 90 degrees as the analytical signal. The biomass is determined without p re-treatment or dilution of the original sample. In the past, the use of unfiltered bioprocess samples in flow injection has been avoided du e to problems associated with a complex sample matrix, e.g., cell aggr egation, clogging of the flow system, cells sticking to tubing walls a nd cross contamination. The sample range for the assay is 0.2 to at le ast 80 g l(-1) biomass with relative standard deviations of <3%. The r esults from a single assay are available 3 min after assay initiation.