Thermodynamic Solubility Assays
- Thermodynamic solubility tests evaluate the solubility of solid crystalline material in aqueous solvent as a saturated solution in equilibrium
- Thermodynamic aqueous solubility tests can be performed in any media or buffer
Kinetic Solubility Assays
- Aqueous kinetic solubility tests evaluate the solubility of a compound already fully dissolved in an organic solvent
- Kinetic solubility tests can be performed in any media or buffer
Fasted State Simulated Gastric Fluid (FaSSGF) pH 1.6 Solubility
- Solubility assay performed in artificial FaSSGF
- This biologically relevant fluid mimics gastric juices because it contains natural surfactants (salts and acids)
Fasted (FaSSIF) and Fed State Simulated Intestinal Fluid (FeSSIF) pH 6.5 Solubility Assays
- Solubility assay performed in artificial FaSSIF/FeSSIF
- This biologically relevant fluid mimics intestinal juice because it contains natural surfactants (bile salts and lecithin)
Partition Coefficient (Log D) Assays
- Log D coefficient is the ratio of concentrations of a compound in the two phases of a mixture of two immiscible solvents at equilibrium
- This method involves dissolving the compound in a known volume of octanol (hydrophobic) and water or PBS (hydrophilic)
- Shake-flask method