Abstract
The physical state, melting behaviour and release rate of aminophylline suppositories were studied during storage. The fraction of non-crystallized fat, assessed by pulse NMR, varies between different vehicles. At room temperature several vehicles do not seem to be completely crystalline. Aging, as observed in prolonged melting time and a reduced release rate, is not expressed in a drastic reduction of the fraction of non-crystallized fat, as observed by NMR. On the contrary the mobility of the protons in the non-crystallized state is likely to offer a more promising tool to monitor aging.
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De Blaey, C.J., Varkevisser, F.A. & Kalk, A. Pulsed proton NMR and solid-liquid fat ratio determinations in suppository vehicles and aminophylline suppositories. Pharmaceutisch Weekblad Scientific Edition 6, 203–208 (1984). https://doi.org/10.1007/BF01999943
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DOI: https://doi.org/10.1007/BF01999943