One of the methods for estimating cell biomass is to calculate dry cell mass. In this example, consider taking a 50 ml sample of bacterial culture from a bioreactor with a 2 L working volume, then pelleting the cells by centrifugation (see image) and carefully discarding the supernatant. The pelleted cells in the centrifuge tube are heated at 90deg C until dried completely. If the empty centrifuge tube weighs 12.5 g and the centrifuge tube with the dry cell pellet weighs 12.62 g, what is the dry cell mass in grams per litre (g/L)?
Added by Montserrat L.
Step 1
Weight of dry cell pellet = Weight of centrifuge tube with dry cell pellet - Weight of empty centrifuge tube Weight of dry cell pellet = 12.62 g - 12.5 g Weight of dry cell pellet = 0.12 g Show more…
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