Log S
LogS is directly related to the water solubility of a drug and it is defined as a common solubility unit corresponding to the 10-based logarithm of the solubility of a molecule measured in mol/L. The solubility and logS of a drug can be divided in:
- Intrinsic solubility (log S 0) - solubility measured after equilibrium between the dissolved and solid state at a pH where the compound is neutral
- pH-dependent solubility - the solvation equilibrium is affected by the solution pH.1
In DrugBank, it is possible to find the experimental and predicted value of logS.
References:
- ChemAxon [Link]
![](https://dev.drugbank.com/rails/active_storage/representations/redirect/eyJfcmFpbHMiOnsibWVzc2FnZSI6IkJBaHBGQT09IiwiZXhwIjpudWxsLCJwdXIiOiJibG9iX2lkIn19--d340925482956c4e6a16c6c193226975caf181eb/eyJfcmFpbHMiOnsibWVzc2FnZSI6IkJBaDdCem9MWm05eWJXRjBTU0lJYW5CbkJqb0dSVlE2QzNKbGMybDZaVWtpQ25nME56ZytCanNHVkE9PSIsImV4cCI6bnVsbCwicHVyIjoidmFyaWF0aW9uIn19--cee43b41e0ba7b27417cc5f7c31bb48545dde7d1/api_card.jpg)