ONS Solubility Book: Edition 2 - with Predicted Values

The Second Edition (2009-12-27) of the Open Notebook Science Solubility Challenge book is now available. The issues with some missing text have been resolved, in addition to providing clickable links for the references in the PDF version.

However, the main difference is the addition of a new section on solubility predictions. The book is now somewhat larger than the first edition, coming in at 129 pages but still very affordable at $8.16 (covers printing and shipping costs from LuLu).

This was added to the preface:

Predicted Solubilities

In this edition, a new section is added to provide predicted solubility values for selected solutes in a range of solvents. Specifically, solutes are included when measurements from at least 5 different solvents are available. A method using Abraham descriptors depends on the experimental solubility measurements from several solvents to make predictions, which is detailed in that section of the book. For this reason, this edition also includes some aqueous solubility measurements, which are generally available from the literature. The focus of this collection remains on non-aqueous solubility.

Consistent with how the experimental measurements are made available, the predicted solubility values are provided as a work in progress. The purpose in providing them is to suggest solvents of interest for various applications. The boiling point of each solvent is also listed in the table to allow a convenient selection. When available, experimental measurements are listed next to the predicted values. This information can be helpful to gauge the usefulness of the model to some extent but does not guarantee its reliability for the other solvents. As more measurements are collected the reliability of the predictions is likely to increase and this will be reflected in future editions of this book.

Andrew Lang has been busily learning about building models using Abraham descriptors. As luck would have it, Michael Abraham just published an extensive collection of his descriptors for many solvents in a recent publication:

Abraham M.H.; Smith R.E.; Luchtefeld R.; Boorem A.J.; Luo R.; Acree Jr. W.E. Prediction of solubility of drugs and other compounds in organic solvents. J. Pharm. Sci. Early View Sept. 22 (2009) http://dx.doi.org/10.1002/jps.21922

This is an important step for the ONS Challenge project by taking us closer to the eventual goal of providing chemists an open tool for anticipating the solubility behavior of their reactants and products in a particular solvent. Researchers might think of trying new solvents after perusing their measured or predicted solubilization potential for a given solute.

We don't know how good the predictions will turn out but we will certainly find out in the coming months and report as we go. Even though the Submeta awards have all been distributed we still welcome measurement contributions.