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Simultaneous X-ray diffraction and calorimetric study of metastable- to-stable solid phase transformation of 1,2-dipalmitoyl-sn-glycerol.

H Takahashi·M Watanabe·P J Quinn·I Hatta
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Abstract

The thermal behaviour and structural changes associated with the phase transformation of 1,2-dipalmitoyl-sn-glycerol (DPG) were studied by means of simultaneous X-ray diffraction and differential scanning calorimetry. Metastable DPG solid phases are crystallized from the melted sample by thermal quenching. The metastable phase (alpha-phase) formed initially is converted into a stable phase (beta' phase) at approximately 50 degrees C on heating. It was found that the behaviour of the alpha- to beta'-phase transformation depends on the thermal history. DPG solid samples incubated at approximately 3 degrees C for more than 10 h after cooling transformed directly into the beta'-phase with heat release. On the other hand, in the solid samples without incubation, the alpha-phase once melted and then the crystallization of the beta'-phase occurred successively from the melted state.

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Calorimetry, Differential ScanningCrystallizationDiglyceridesMolecular ConformationTemperatureThermodynamicsX-Ray DiffractionJournal ArticleResearch Support, Non-U.S. Gov't

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H Takahashi, M Watanabe, P J Quinn, I Hatta. 1999-03-29. Simultaneous X-ray diffraction and calorimetric study of metastable- to-stable solid phase transformation of 1,2-dipalmitoyl-sn-glycerol.. https://doi.org/10.1016/s0301-4622(99)00021-6

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