AAT Bioquest

What is EC50?

Posted February 13, 2020


EC50 (also written as [A]50) stands for half maximal effective concentration. It is a measure of the concentration of a drug at which 50% of its maximal response is induced and can be determined from the inflection point where the rate of increase in response with respect to the ligand concentration goes down. EC50 and IC50, albeit conceptually similar, have differences in their notions. For a better understanding, check out what is the difference between EC50 and IC50.

Additional resources

EC50 Calculator