title: Pulsed proton NMR and solid-liquid fat ratio determinations in suppository vehicles and aminophylline suppositories.
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.
mesh_terms: D000628:Aminophylline / Q000008:administration & dosage / Q000032:analysis*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004355:Drug Stability; D004356:Drug Storage; D005223:Fats / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D010316:Particle Size; D014677:Pharmaceutical Vehicles; D013488:Suppositories; D013696:Temperature
chemical_list: D005223:Fats; D014677:Pharmaceutical Vehicles; D013488:Suppositories; D000628:Aminophylline