title: Combined dipyridamole and aspirin pellet formulation for improved oral drug delivery. Part 1: Development pharmaceutics.
abstract: The dissolution profile of various weight fractions of dipyridamole: hydropropylmethylcellulose acetate succinate (HPMC-AS) and dipyridamole: hydroxypropylmethylcellulose phthalate co-precipitates lead to the choice of 1:2 dipyridamole: HPMC-AS as the controlled-release component. It was deposited to form two-third of the total dose as an inner layer on inert sucrose cores by air suspension coating for release mainly in the small intestine. Further examination of this material by IR spectroscopy, differential scanning calorimetry and X-ray diffraction indicated some free drug, preferentially soluble under gastric pH conditions. One-third of the total dose was applied by pan coating as an outer layer of micronized dipyridamole around the inner enteric co-precipitate layer. Aspirin-loaded cores were prepared also by pan coating for use in the final product, which contained both anti-platelet drugs.
authors.affiliation: Department of Pharmaceutics, Trinity College, University of Dublin, Ireland.
authors.forename: P B
authors.initials: PB
authors.lastname: Deasy
authors.forename: P W
authors.initials: PW
authors.lastname: Murtagh
mesh_terms: D001241:Aspirin / Q000008:administration & dosage* / Q000737:chemistry; D002152:Calorimetry, Differential Scanning; D004176:Dipyridamole / Q000008:administration & dosage* / Q000737:chemistry; D004338:Drug Combinations; D004339:Drug Compounding / Q000379:methods; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage* / Q000737:chemistry; D012995:Solubility; D013055:Spectrophotometry, Infrared; D013535:Suspensions; D014961:X-Ray Diffraction
chemical_list: D004338:Drug Combinations; D010975:Platelet Aggregation Inhibitors; D013535:Suspensions; D004176:Dipyridamole; D001241:Aspirin