Question

You are given a vial of cells at a density of 6.8 x 10^6 cells/ml. You are asked to seed a 12 well plate, which requires 2 x 10^5 cells per well. Because every well requires a final media volume of 1mL, your professor asks you to dilute your cells with media so that you can directly add 1ml of diluted cells per well in the plate. How you would dilute your cells so that each well receives 2 x 10^5 cells per well? SHOW OR EXPLAIN YOUR WORK. Be sure to write down what your dilution factor would be and how you would create this dilution (cell mix volume + media volume). Note: Media is very expensive! You only need 12mL of diluted cell mixture for your experiment to load all 12 wells in the plate. Do not make more than 18mL of diluted cell mixture.

Please go step by step so I can understand how to get through the problem. Thank you very much!!!

Answer 1

1. Hair we are going to determine the dilution with simple equation V1xC1=V2xC2 Where V1 and C1 are the volume and concentration of stock of cells provided as V2 an C2 is the same for the required diluted cell sample

2. As calculated from the equation, we will take 0.53 ml i.e. 530 microlitres of stock (6.8 x 10^6 cells/ml) and mix with 17.47 ml of media to get 18 ml of 2 x 10^5 cells/ml of dilluted cell.

3. Next we will distribute 1 ml of this diluted cell into each of the 12 wells, hence 12ml will be used and rest 6 ml of the diluted sample will be left over.

4. Dilution factor (DF) is calculated as the ratio of final volume to the initial volume:

DF = (volume of stock)/ ( volume of diluted sample)

DF= 1/18= 0.055......