Prism Ic50 Standard Error
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Graphpad.com FAQs Find ANY word Find ALL words Find EXACT phrase How should I compute an "average" EC50 for several experiments? How can I express its uncertainty or standard deviation? FAQ# 534 Last Modified 1-January-2009 If you used the one-site competition or sigmoid dose-response
Convert Log Ec50 To Ec50
curve-fit models, you presumably used X values (concentrations) that were equally spaced on a log how to calculate ic50 in graphpad prism scale (e.g., 1, 3, 10, 30, 100, 300...). The midpoint that Prism computes is the logEC50, which will have a distribution closer to
Ic50 Excel
a Gaussian distribution than will the EC50. Therefore, you should average the logEC50 values, not the EC50 values. Since the distribution of EC50s is usually not symmetrical, the mean of the EC50s is not a good way to what is a good ic50 value pool the data. Since some people have trouble thinking about logarithms, it is conventional to report the antilog of the mean of the logEC50 values. This is the same as the geometric mean of the EC50 values, and it is expressed in the same concentration units as the EC50. An alternative is to report the median, rather than the mean. If you have an odd number of values, the median of the EC50 will be equivalent to ec50 calculation example the mean of the logEC50. If you have an even number of values, then the median involves taking the mean of the middle two values, so the result will be a bit inconsistent in the EC50 and logEC50 scales, but the difference is not likely to be huge. What about quantifying the scatter? You can compute the SD orSEMof the logarithms of the EC50, and report the mean logarithm of the EC50 along with the SD or SEM of the logEC50 values. This makes sense, but some scientists are confused by logs. If you take the antilog of theStandard Errorof the logEC50, you get a puzzling number. Is not a value you can add to and subtract from the meanEC50. Instead,you candivide and multiply by that number. So if you take the antilog of the se of the logec50, the result is multiplied and divided by the geometric mean to give a sense of error. It is a multiply/divide factor, not a plus/minus standard error. This is conceptually sound, but not commonlh done. Here is a more conventional approach. Forget the SE of the logEC50s. Or rather, use the SE to compute the 95% confidence interval of the logec50. Then antilog both limits to get the confidence interval of the EC50 -- which will not be symmetrical around the ec50 itself. Here is an example. Five repeate
deviation for IC50 calculation? We use Graph Pad Prism for IC50 calculations. This program reports standard error for logIC50 but not for the IC50 itself. So my question is, how
Pic50
do you report standard deviation for IC50 with Prism or which program gives how to calculate ic50 value you this value? Topics IC50 × 235 Questions 59 Followers Follow GraphPad Prism × 58 Questions 53 Followers Follow
How To Calculate Ic50 From Excel Graph And The Xy Equation
Medicinal and Pharmaceutical Chemistry × 718 Questions 35,826 Followers Follow Natural Product Pharmacology × 183 Questions 1,321 Followers Follow Bioactive Compounds × 176 Questions 1,883 Followers Follow Mar 17, 2014 Share Facebook https://graphpad.com/support/faq/how-should-i-compute-an-average-ec50-for-several-experiments-how-can-i-express-its-uncertainty-or-standard-deviation/ Twitter LinkedIn Google+ 0 / 0 All Answers (5) Danilo Zangani · INSERM U 1088 multiply the std error given automatically by Prizm by the the result of the square root of 3 (or sample number) and you'll get the std deviation. It's going to be bigger, but it is the simplest way. Mar 17, 2014 Mohanraj Ramachandran · Uppsala University to make it simple https://www.researchgate.net/post/How_to_report_standard_deviation_for_IC50_calculation SE= SD/ root of no of samples. So you can calculate back SD from this. Mar 18, 2014 Natalia Paola Alza · National Scientific and Technical Research Council Thanks for your answers! But the problem is that I will have the IC50 value as concentration units and its standard deviation as log. How can I do to have standard deviation in concentration units? Mar 18, 2014 Ali Zarezadeh · University of Florida You can find the answer here: http://www.graphpad.com/support/faqid/1162/ Apr 18, 2014 Can you help by adding an answer? Add your answer Question followers (17) See all Erik Maronde Goethe-Universität Frankfurt am Main Danilo Zangani INSERM U 1088 Henrik Rasmus Andersen Technical University of Denmark Atanas G Atanasov University of Vienna Ali Zarezadeh University of Florida Jecinta Ndiombueze Anowu Federal University of Agriculture, Makurdi Agnieszka Joanna Brodowska Lodz University of Technology Mohanraj Ramachandran Uppsala University Farid Abrigach Université Mohammed Premier Natalia Paola Alza National Scientific and Technical Research Council Views 4205 Followers 17 Answers 5 © 2008-2016 researchgate.net. All rights reserved.About us · Contact us · Careers · Developers · News · Help Center · Privacy · Terms · Copyright | Advertising · Recruiting We use cookies to give you the best possibl
to store and analyze their dose response data from in-vitro assays. Now that the automated calculations extension of CDD Vision supports the calculation of pCI50 values, I’d like to convince users of IC50 to consider using https://www.collaborativedrug.com/buzz/2014/07/14/why-using-pic50-instead-of-ic50-will-change-your-life/ pIC50 instead, and why it will make your life easier (in the long run), and just make you a finer human being. I’ve worked in two small biotech companies where I was heading up both biology and informatics, and thus was able to “force” the use of pIC50 values instead of IC50 values. You would have thought I said from now on we will be eating bugs for lunch. It was a bit of an uphill how to battle, and there is a learning curve, but after six months, everyone was used to it, agreed it was better, and wouldn’t go back. Oh yeah, and it’s just plain “the right thing to do”. What is a pIC50? It’s the negative log of the IC50 value in molar. Watch: An IC50 of 1 µM is 10-6 M, which is pIC50 = 6.0 An IC50 of 1 nM is 10-9 M, which is pIC50 = 9.0 An how to calculate IC50 of 10 nM is 10-8 M, which is pIC50 = 8.0 An IC50 of 100 nM is 10-7 M, which is pIC50 = 7.0 An IC50 of 30 nM is 3 x10-7 M, which is also 10-7.5 M, which is pIC50 = 7.5 Do you see a pattern? You’re in drug discovery… you’ve been working with pH since you were knocking over graduated cylinders in high school. When working in the lab, did you say that this solution has an acidity of 10 µM (10-5 M) [H+]? Of course not. You talked about a solution at pH 5. And you didn’t bother trying to back calculate in your head … that is, you didn’t try and convert a pH value of 7.5 to 30 nM [H+]. That’s because you’ve trained yourself to think in terms of pH, as well as the fact that the acidity of an aqueous solutions is a logarithmic function. pH values in experiments go from 1 to 2 to 3, not 10 mM to 20 mM to 30 mM [H+]. That is exactly the way you should think about IC50 values (or when testing agonists, EC50 values). Dose dependent inhibition (or activation) of an enzyme or cell is a logarithmic phenomenon (with regard to compound concentration), so it makes more sense to view the data this way. And if you look at papers from
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