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Download fileControl of Crystal Modification and Crystal Shape by Control of Solid–Solid Transitions during Crystallization and Drying: Two Industrial Case Studies
journal contribution
posted on 2016-02-19, 17:53 authored by Fabrice Dufour, Benjamin Stichel, J. Ian GraysonCrystallization and drying are the final steps in the
manufacture
of most drug substances that determine their final features and may
also impact the manufacture of the formulated drug product. It is
important to understand and control the mechanisms involved in the
crystallization and drying processes to avoid handling and formulation
problems, and this is illustrated with two examples of large-scale
processes. In the first, a solid–solid phase transition between
two very similar crystalline forms was shown to lead to dramatic particle
size reduction and consequent processing issues; the unwanted phase
transition was avoided by careful choice of crystallization conditions.
In the second, control of the drying conditions allowed a rapid solid–solid
phase transition of a mixed solvate into a stable anhydrous form.