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			| Dealing with multiple "0% inhibition" results in HTS tests [message #1603] | Thu, 28 April 2022 11:25  |  
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					|  Christophe Messages: 34
 Registered: January 2022
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	| Hello everyone 
 In medicinal chemistry, batches of molecules are tested using high-throughput screening methods constraint with a concentration threshold. For example, the whole batch is used at 1 µM and an efficacy (e.g. % inhibition) is measured at this concentration.
 
 DW allows to calculate a ligand efficiency with these results. This is to be taken with caution as it requires extrapolating a delta G from the % inhibition.
 
 My question: How to deal with molecules that are below their effective concentration (0% inhibition) and for which no ligand efficiency can be calculated? These molecules (more exactly all these zero results) may prevent the calculation of important parameters and/or ruin analyses such as Partial Least Squared Regression for example.
 Should one remove all these zeros and retain only the molecules with activity? Is there a reasonable way to code these molecules so that the structural information they carry can still be used in some analyses?
 I tried to use categorical variables and it helped for a bit. But does anyone have more experience in this area than I do?
 Thanks
 Best regards
 
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