Solid-state β-cyclodextrin complexes containing indomethacin, ammonia and water.: I.: Formation studies

Five complexes were prepared with beta-cyclodextrin and the insoluble, non-steroidal, anti-inflammatory drug indomethacin. The complexes were found to contain drug, water and ammonia in several unique combinations. It was theorized the complexes were tri-molecular in nature and their formation was controlled by a hydrophobic/hydrophilic balance created within the beta-cyclodextrin ring cavity prior to complex formation. Each complex was characterized by ultraviolet, infrared, nuclear magnetic resonance, powder X-ray diffraction, differential scanning calorimetry, and thermogravimetric techniques. These characterizations revealed distinct differences among the five complexes. (C) 1998 Elsevier Science B.V. All rights reserved.