Module 1
December 16, 2022 12:23 PM
Serial Dilution Calculations
Ex. 1 mL of culture is diluted in 9 mL of water to make a first dilution of 1:10. what dilution would result for
the 3rd repetition of this process?
If first dilution is 1:10, then second is 1:100, so third is 1:1000
• CFU = colony forming unit
# 𝑐𝑜𝑙𝑜𝑛𝑖𝑒𝑠 𝑓𝑜𝑟𝑚𝑒𝑑
• 𝐶𝐹𝑈 =
𝑚𝐿 𝑝𝑙𝑎𝑡𝑒𝑑 ×𝑑𝑖𝑙𝑢𝑡𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟
December 16, 2022 12:23 PM
Serial Dilution Calculations
Ex. 1 mL of culture is diluted in 9 mL of water to make a first dilution of 1:10. what dilution would result for
the 3rd repetition of this process?
If first dilution is 1:10, then second is 1:100, so third is 1:1000
• CFU = colony forming unit
# 𝑐𝑜𝑙𝑜𝑛𝑖𝑒𝑠 𝑓𝑜𝑟𝑚𝑒𝑑
• 𝐶𝐹𝑈 =
𝑚𝐿 𝑝𝑙𝑎𝑡𝑒𝑑 ×𝑑𝑖𝑙𝑢𝑡𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟
