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Updated: Jul 17, 2026

Solubility of Hydrophobic Compounds in Aqueous Solution Using Combinations of Self-assembling Peptide and Amino Acid
Published on: September 20, 2017
Automated approach to couple solubility with final pH and crystallinity for pharmaceutical discovery compounds
Christopher Seadeek1, Howard Ando, Shobha N Bhattachar
1Pfizer Global Research and Development, 2800 Plymouth Road, Ann Arbor, MI 48105, USA. Chris.Seadeek@Pfizer.com
Abstract:
The design and validation of a novel high-throughput system for thermodynamic solubility determination requiring only 5 mg of sample is described. The system uses a sintered nickel filter assembly to recover excess solids from saturated solutions for rapid crystallinity assessment via powder X-ray diffraction (PXRD). Moreover, the system measures the pH of filtrates to provide a final pH value with the solubility measurement. The limit of detection for the UV-vis plate reader used on this system is approximately 0.001 mg/ml, while the practical upper limit is approximately 3 mg/mL. The solubility measurements of 60 proprietary Pfizer compounds were used to validate the nickel filter assembly against a more conventional polyvinylidenedifluoride (PVDF) filter. Additionally, a comparison was made between a subset of 10 compounds run on the automated system and a more traditional shake-flask method employing HPLC analysis. In both cases, a favorable comparison was obtained.
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