Pallipurath, AR orcid.org/0000-0002-9778-5160, Civati, F, Sibik, J et al. (4 more authors) (2017) A comprehensive spectroscopic study of the polymorphs of diflunisal and their phase transformations. International Journal of Pharmaceutics, 528 (1-2). pp. 312-321. ISSN 0378-5173
Abstract
Understanding phase transitions in pharmaceutical materials is of vital importance for drug manufacturing, processing and storage. In this paper we have carried out comprehensive high-resolution spectroscopic studies on the polymorphs of the non-steroidal anti-inflammatory drug diflunisal that has four known polymorphs, forms I–IV (FI–FIV), three of which have known crystal structures. Phase transformations during milling, heating, melt-quenching and exposure to high relative humidity were investigated using Raman and terahertz spectroscopy in combination with differential scanning calorimetry and X-ray powder diffraction. The observed phase transformations indicate the stability order FIII > FI > FII, FIV. Furthermore, crystallization experiments from the gas phase and from solution by fast evaporation of different solvents were carried out. Fast evaporation of an ethanolic solution below 70 °C was identified as a reliable and convenient method to obtain the somewhat elusive FII in bulk quantities.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Keywords: | Diflunisal; Phase transformation; Polymorphs; Terahertz spectroscopy |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemical & Process Engineering (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 18 Feb 2020 13:58 |
Last Modified: | 18 Feb 2020 13:58 |
Status: | Published |
Publisher: | Elsevier |
Identification Number: | 10.1016/j.ijpharm.2017.06.020 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:157233 |