Differential Coefficient Method (theoretical)

  • Automatic method
    • Still need to input colony radius range (in case of contaminants)
  • Count number of colonies over a wide range of sensitivities
  • If number of colonies detected is plotted as a function of the sensitivity setting, the curve resembles a logarithmic curve if the plate was sparsely populated.
  • In these cases, there might be some derivative value threshold that we can employ to obtain the optimal sensitivity value.
  • This will be much faster than the Equal Areas Method on sparse plates.