You have 4 ml of a cell suspension with a concentration of 5.9 × 10⁵ cells/ml.  You need to make up 2 ml of cells at a concentration of 1 × 10⁶ cells/ml.  What volume of the original cell suspension will you need to make up 2 ml of cells at a 1 × 10⁶ cells/ml? ml. (Answer to 2 decimal places.)

As you need 2 mls of cells at the desired concentration you centrifuge and pallet your cells, and then remove the liquid from the pallet.  How much buffer do you need to add to these cells to make up 2 ml of cells at 1 ×10⁶ cells/ml? μl.

(Check the units carefully.  If you are not sure how to use C₁V₁ = C₂V₂ to answer this question refer to the information in the Numbers, graphs and calculations eBook.)