Lesson plan

IC50

Half maximal inhibitory concentration (IC 50 ) 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%. The biological component could be an enzyme, cell, cell receptor or microbe. IC 50 values are typically expressed as molar concentration. IC 50 is commonly used as a measure of antagonist drug potency in pharmacological research. IC 50 is comparable to other measures of potency, such as EC 50 for excitatory drugs. EC 50 represents the dose or plasma concentration required for obtaining 50% of a maximum effect in vivo. IC 50 can be determined with functional assays or with competition binding assays. Sometimes, IC 50 values are converted to the pIC 50 scale. : \ce{pIC_{50}} = -\log_{10} \ce{(IC_{50})} Due to the minus sign, higher values of pIC 50 indicate exponentially more potent inhibitors. pIC 50 is usually given in terms of molar concentration (mol/L, or M), thus requiring IC 50 in units of M. The IC 50 terminology is also used for some behavioral measures in vivo, such as the two bottle fluid consumption test.…

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Article summary

Half maximal inhibitory concentration (IC 50 ) 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%. The biological component could be an enzyme, cell, cell receptor or microbe. IC 50 values are typically expressed as molar concentration. IC 50 is commonly used as a measure of antagonist drug potency in pharmacological research. IC 50 is comparable to other measures of potency, such as EC 50 for excitatory drugs. EC 50 represents the dose or plasma concentration required for obtaining 50% of a maximum effect in vivo. IC 50 can be determined with functional assays or with competition binding assays. Sometimes, IC 50 values are converted to the pIC 50 scale. : \ce{pIC_{50}} = -\log_{10} \ce{(IC_{50})} Due to the minus sign, higher values of pIC 50 indicate exponentially more potent inhibitors. pIC 50 is usually given in terms of molar concentration (mol/L, or M), thus requiring IC 50 in units of M. The IC 50 terminology is also used for some behavioral measures in vivo, such as the two bottle fluid consumption test.…

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Discussion questions

  1. Summarise the article in your own words. Which single claim would you verify first, and why?
  2. Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
  3. If two sources disagreed about one of these facts, what would you need in order to trust one over the other?

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Key claims and bibliography are generated from the same tracked claims and sources as the article page.