Structural and analytical characterization of three hydrates and an anhydrate form of risedronate.
Four hydration states are reported for Risedronate monosodium. A single-crystal X-ray structure determination is provided as proof of assignment for the monohydrate, hemi-pentahydrate, and variable hydrate forms. The structure provided for the anhydrate form was determined through simulating annealing calculations and subsequent Reitveld refinement of a high-quality X-ray powder diffraction patterns Favorable comparisons of experimentally obtained X-ray powder patterns are made to those generated from the single crystal data. Characteristic infrared, Raman, and NMR spectra are provided and discussed for each form as are thermal analysis profiles. In addition, photomicrographs are provided for each of the forms isolated for this study. The hemi-pentahydrate is demonstrated to be the equilibrium form at room temperature and 37 degrees C, in the presence of water.
Redman-Furey
Nancy
N
Procter & Gamble Pharmaceuticals, Inc., P.O. Box 191, Norwich, New York 13815, USA. redmanfurey.nl@pg.com
Dicks
Michael
M
Bigalow-Kern
Adrienne
A
Cambron
R Thomas
RT
Lubey
Gwen
G
Lester
Cathy
C
Vaughn
Dana
D
D000042:Absorption; D018360:Crystallography, X-Ray; D004055:Differential Thermal Analysis; D012968:Etidronic Acid / Q000031:analogs & derivatives* / Q000737:chemistry*; D005079:Excipients; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D000068296:Risedronic Acid; D013055:Spectrophotometry, Infrared; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman
D005079:Excipients; D000068296:Risedronic Acid; D012968:Etidronic Acid