Determination of Water-Solvent Partition Coefficients for Fluorescein: Evaluation of Descriptors for the Lactone Form and Prediction of Properties

We have determined water-solvent partition coefficients, P, at 298 K for fluorescein at an aqueous pH 3.28 for the solvents octan-1-ol, dichloromethane, trichloromethane, 1,2-dichloroethane, toluene, chlorobenzene and bromobenzene. The log(10)P values were then used to obtain descriptors for the lactone form of fluorescein. These descriptors are not exceptional except that the hydrogen-bond acidity, A, of fluorescein is a little higher than expected for a species with two phenolic groups. The descriptors allow the prediction of further log(10)P values for the lactone form in a large number of water-solvent systems as well as the prediction of physico-chemical and environmental properties of fluorescein.

Automated summary

Experimentally determined water-solvent partition coefficients of fluorescein were used to obtain descriptors for predicting the properties of fluorescein.