Dr. Butthead received a new cell line and he wants to see which culture media grows the cells the best. He cultures them in a supplemented (s) and complete (c) media. After 2 days he dilutes a sample from each flask 1/2 (100uL of cells + 100 uL of trypan blue) His hemacytometer counts for S are 15,14,19,12 and C are 92,100,95,and 84. 1. Which is the concentration of cells in each flask? (cell per mL) 2. Which media works best? explain why? 3. cells must be fed if they are too concentrated (ie 1x10^6 cells/ml). Does either flask need to be fed? if yes why and describe how to dilute the cells to 5x10^4 cell/ml in a volume of 10 mL. Thank you for your help Solution 1. Which is the concentration of cells in each flask? (cell per mL) Dilution factor =2 Supplemented (s) Cell/mL=(15+14+19+12)/4 x dilution factor x 10^ 4 =30 x 10^ 4 cells/mL Complete (c) media Cell/mL=(92+100+95+84)/4 x dilution factor x 10^ 4 =185.5 x 10^ 4 cells/mL 2. Which media works best? explain why? Complete (c) media works best since it promotes cell proliferation better than supplemented media. 3. cells must be fed if they are too concentrated (ie 1x10^6 cells/ml). Does either flask need to be fed? if yes why and describe how to dilute the cells to 5x10^4 cell/ml in a volume of 10 mL. Cells in the Complete (c) media needs to be fed since the it is too concentrated Stock of cells = 185.5 x 10^ 4 cells/mL Required = 5 x10^4 cell/ml Volume = 10 mL C1V1= C2V2 (stock) (required) V1=C2V2/C1 V1 = ( 5 x10^4 X 10 mL )/ 185.5 x 10^ 4 =0.27 mL 0.27 mL of stock + 9.73 mL of media gives 10 mL of media with 5 x10^4 cell/ml concentration.