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Updated: Aug 13, 2026

X-ray Powder Diffraction in Conservation Science: Towards Routine Crystal Structure Determination of Corrosion Products on Heritage Art Objects
Published on: June 8, 2016
New applications of electron diffraction in the pharmaceutical industry: polymorph determination by using a
Z G Li1, R L Harlow, C M Foris
1Central Research & Development, Science & Engineering Laboratory, Experimental Station, DuPont Company, Wilmington, DE 19880-0228, USA.
Abstract:
Electron diffraction has been recently used in the pharmaceutical industry to study the polymorphism in crystalline drug substances. While conventional X-ray diffraction patterns could not be used to determine the cell parameters of two forms of the microcrystalline GP IIb/IIIa receptor antagonist roxifiban, a combination of electron single-crystal and synchrotron powder diffraction techniques were able to clearly distinguish the two polymorphs. The unit-cell parameters of the two polymorphs were ultimately determined using new software routines designed to take advantage of each technique's unique capabilities. The combined use of transmission electron microscopy (TEM) and synchrotron patterns appears to be a good general approach for characterizing complex (low-symmetry, large-unit-cell, micron-sized) polymorphic pharmaceutical compounds.
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