عنوان

X-Ray Diffraction of Pharmaceutical Materials

9780122608308

b606473

X-Ray Diffraction of Pharmaceutical Materials

[Book]

Harry G Brittain Affiliation: Center for Pharmaceutical Physics 10 Charles Road Milford, NJ 08848, USA

The chapter examines the processes associated with the ability of a crystalline solid to act as a diffraction grating for the electromagnetic radiation termed 'x-rays'. The chapter discusses the practice of x-ray diffraction as applied to the characterization of single crystals and to the study of powdered crystalline solids. The diffraction of x-rays by crystalline solids was originally used to deduce the nature of the electromagnetic radiation. Such diffraction has now become a commonly applied tool for the structural characterization of single-crystals and polycrystalline powders. Owing to the presence of the functional groups present in drug substance molecules that promote their efficacious action, the crystallization possibilities for such materials can be wide-ranging, leading to possibilities for polymorphism and solvatomorphism. X-ray powder diffraction (XRPD) represents the methodology of choice for the crystallographic characterization of drug substances produced on a routine, batch-type basis. Properly prepared samples yield powder patterns that contain a scattering peak for each crystal plane/face, and therefore, constitute an identification test for a given crystalline phase. Since polymorphism and solvatomorphism are crystallographic occurrences, XRPD will always be the primary determinant of the existence of such phenomena. Variable temperature XRPD is a valuable tool to understand thermally-induced reactions, and to characterize materials during the conduct of stability studies.

Harry G Brittain Affiliation: Center for Pharmaceutical Physics 10 Charles Road Milford, NJ 08848, USA

Harry G Brittain Affiliation: Center for Pharmaceutical Physics 10 Charles Road Milford, NJ 08848, USA

[Book]

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