To subculture cells you must plate the cells on a new plates

To subculture cells, you must plate the cells on a new plates at a specific density that depends on that cell line and the purpose of your experiment. If you needed to plate the cells(ie. That your group resuspended in 500microliters) at a concentration of 2200 cells per cm2 onto 35mm plates that have an effective growth surface area of 9cm2, how would you do this? The final volume of media for a 35mm plate is 2mL.
Total # of 35mm culture dishes plated?
Volume of media to add to cell suspension?
Please explain throughly
Thank you

Solution

The information regarding the initial number of cells \"(ie. That your group resuspended in 500 microliters)\" is misssing in the question. Hence, I will solve this question making an assumption that the total number of cells \"that your group resuspended in 500 microliters\" was N. So, the stock seed contains N/500 cells/L = 2N cells/mL.

Given that,

1. the cells are to be plated at a concentration of 2200 cells per cm², and

2. the plate has an effective growth surface area of 9 cm² (= 2 mL).

Thus total number of cells required = 2200 × 9 = 19,800 cells.

The stock contains 2N cells/mL. Thus, the amount of seed needed for obtaining 19,800 cells = 19800/2N = 9900/N mL

Hence, you should take 9900/N mL of seed and dilute it with [2-(9900/N)] mL of medium to get final 2 mL of cell suspension for plating the 35 mm plate.

If for example the initial number of cells \"that your group resuspended in 500 microliters\" was 10⁴ (i.e. N = 10⁴), then you must take 9900/10⁴ = 0.99 mL (990 L) of the stock seed, dilute it with (2-0.99) = 1.01 mL (1010 L) of medium to get final 2 mL of cell suspension for plating the 35 mm plate.