title: Enhancement of water solubility of indomethacin by complexation with protein hydrolysate.
abstract: Complex formation between indomethacin (Indo) and casein hydrolysate was developed as a novel technique for enhancing the water solubility of Indo. The complex (Indo-Pep) was prepared by mixing an ethanol solution of Indo and an aqueous solution of peptide mixture, followed by lyophilization. The water solubility of Indo-Pep under weakly acidic and neutral conditions is much higher than that of Indo alone. The water solubility of Indo increased with increasing quantity of peptide. Characterization of Indo-Pep using scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction showed that Indo was incorporated in Indo-Pep in an amorphous state. The fluorescence quenching of Indo-Pep also suggested complexation between Indo and the peptides. An aqueous solution of Indo-Pep was fractioned by centrifugation followed by filtration using membrane filters and ultrafilters. Analysis of the fractions by dynamic light scattering and ultraviolet-visible spectroscopy showed that Indo-Pep consisted of small particles and was not a hydrocolloidal material.
authors.affiliation: Department of Applied Chemistry, Faculty of Engineering, University of Miyazaki, 1-1 Gakuen Kibanadai Nishi, Miyazaki 889-2192, Japan.
authors.forename: Asuka
authors.initials: A
authors.lastname: Inada
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Oshima
authors.forename: Hiromi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Yoshinari
authors.initials: Y
authors.lastname: Baba
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry*; D002364:Caseins / Q000737:chemistry*; D007213:Indomethacin / Q000737:chemistry*; D011492:Protein Hydrolysates / Q000737:chemistry*; D012995:Solubility; D014867:Water / Q000737:chemistry
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D002364:Caseins; D011492:Protein Hydrolysates; D014867:Water; D007213:Indomethacin
keywords: Complex; Dissolution; Indomethacin; Peptide; Solubility