I performed a plaque assay with Bovine Enterovirus and understand how to calculate the PFU, but am unsure which wells to use to calculate it. We only used one well for each dilution in the series, so I can't average the wells. Generally, the examples that I have found on the internet and in textbooks have from 20-50 plaques, but the largest number I have is 16. For one dilution, for example, from the 10^-2 to the 10^-7 dilutions there were 16, 10, 5, 0, 0 plaques produced. For the other results (it was a time-series) I have used the wells where there were more than 10 plaques, but I am not sure for this one as the dilutions were lower (I think something must have gone wrong during the experiment, since the pfu is so much lower at this time-point). e.g. for later time-point, I used 10^-4 to 10^-7 dilutions and got 0, 12 and 2 plaques and have used the plaque number and dilution from the well with 12 plaques.
Sorry if this is confusing, can anyone suggest the best well to use?
Edited by kba, 15 January 2011 - 08:53 AM.