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Updated: Aug 19, 2026

A Package of Established Analytical Tools to Investigate the Solid-State Alteration of Lipid-Based Excipients
Published on: August 9, 2022
Structure determination of the stable anhydrous phase of alpha-lactose from X-ray powder diffraction
Cyril Platteau1, Jacques Lefebvre, Frederic Affouard
1Laboratoire de Dynamique et Structure des Matériaux Moléculaires (UMR CNRS 8024), UFR de Physique, Bâtiment P5, Université des Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq CEDEX, France.
Abstract:
The stable anhydrous form of alpha-lactose has been obtained by the dehydration of alpha-lactose monohydrate in methanol. An X-ray powder diffraction pattern was recorded at room temperature with a laboratory diffractometer equipped with an INEL curved sensitive detector CPS120. The starting structural model of this form was found by a Monte-Carlo simulated annealing method. The structure was obtained through Rietveld refinements and the minimization of crystalline energy for the localization of the H atoms of the hydroxyl groups. Soft restraints were applied to bond lengths and angles. Networks of O-H...O hydrogen bonds account for the crystalline cohesion. A comparison is made between the hydrogen-bond networks of this form and those of the monohydrate and hygroscopic anhydrous forms of alpha-lactose.
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