Half maximal inhibitory concentration (IC50) is a measure of the potency of a substance in inhibiting a specific biological or biochemical function. IC 50 is a quantitative measure that indicates how much of a particular inhibitory substance (e.g. drug) is needed to inhibit, in vitro, a given biological process or biological component by 50%. [1] .

The concepts of IC50 and EC50 are fundamental to pharmacology. The EC50 is the concentration of a drug that gives half-maximal response. The IC50 is the concentration of an inhibitor where the response (or binding) is reduced by half.

This online calculator is used to determine and graph the IC50 (half maximal inhibitory concentration) value given a set of experimental data. Data can be from Excel or CSV. Calculator gives equation of four-parameter logistic (4PL) curve as …

The IC50 (half-maximal inhibitory concentration) value is a measure of the concentration of a drug or compound required to inhibit a particular biological or biochemical process by 50%. From: Journal of Inorganic Biochemistry, 2023

Sep 1, 2016 · Half-maximal inhibitory concentration (IC50) is the most widely used and informative measure of a drug's efficacy. It indicates how much drug is needed to inhibit a biological process by half, thus providing a measure of potency of an antagonist drug in pharmacological research.

Dec 31, 2019 · IC50 stands for inhibitory concentration 50%. That is, the concentration of inhibitor required to reduce the biological activity of interest to half of the uninhibited value. Because it does not directly measure a binding equilibrium, IC50 is less precise than Ki or Kd.

While EC50 quantifies the activation of a receptor by an agonist, IC50 measures the potency of inhibitors. The IC50 value is the concentration of an inhibitor that reduces a biological process by 50%. These inhibitors might block enzyme activity, receptor binding, or …

IC50 is commonly used as a measure of drug potency in whole cell assays. IC50 assays are also used for screening in target-based drug discovery campaigns. Tool for Prediction of pIC50 values (negative log of the IC50 value) from the IC50 values (Sanjeev’s Lab, 2016) 50% of what? How exactly are IC50 and EC50 defined? (GraphPad, 2010)

The IC 50 Tool Kit allows biological dose-response data (such as the rate of an enzyme-catalysed reaction versus the concentration of an inhibitor) to be plotted and fitted to the following curve types to give the mid-point ligand concentration, c (below), or IC 50. The Hill coefficient, or d (below), is now also given.

Mar 6, 2025 · IC 50 measures inhibition of a function and conversely, EC 50 measures activation or induction of a response. Confusing these values can lead to misinterpretation of assay results and costly rework. Let’s take a closer look at each one. Kd stands for dissociation constant, and it measures the binding affinity between the two molecules.