title: Spray drying as a fast and simple technique for the preparation of extended release dipyridamole (DYP) microparticles in a fixed dose combination (FDC) product with aspirin.
abstract: BACKGROUND
  Recent advances have proven that the combinational therapy of extended release dipyridamole (DYP) and fast release aspirin (ASP) can improve clinical indices of heart failure in several vascular disorders. Although pharmaceutical industries always supported fast, simple and cost saving techniques in their productions, there is no simple reported method available for this purpose. The aim of this study was to check the possibility of preparing a FDC product, containing individual dosage units of extended release DYP microparticles and fast release ASP, using the spray-drying technique as a practice compatible with pharmaceutical industries.
  
  
  METHODS
  Solid dispersions of DYP in different polymeric substances (ethyl cellulose, carnauba wax, and Eudragit PO 100), were prepared using the spray-drying method. The physicochemical properties and structure of the prepared microparticles were analyzed using different techniques, such as the particle size analyzer (PSA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X ray diffraction (XRD), and USP dissolution tester. ASP tablets were prepared individually and tested according to pharmacopeia.
  
  
  CONCLUSIONS
  Results showed that prepared microparticles measured about 2.3 µm in size. Statistical analysis of the release data revealed that there is no significant difference in the mean release amount of the selected formulation compared to the innovative brand (Aggrenox®).
  
  
  CONCLUSIONS
  Findings proposed a new formulation (F7) as an alternative to innovative brand and proved spray drying as a practice compatible with pharmaceutical industries and as a successful method for sustaining the DYP release rate from prepared microparticles in a FDC dosage form.
authors.affiliation: Pharmaceutical Technology Laboratory, Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: H
authors.initials: H
authors.lastname: Hamishehkar
authors.affiliation: Biotechnology Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: H
authors.initials: H
authors.lastname: Valizadeh
authors.affiliation: Students' Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: P
authors.initials: P
authors.lastname: Alasty
authors.affiliation: Pharmaceutical Technology Laboratory, Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: F
authors.initials: F
authors.lastname: Monajjemzadeh
mesh_terms: D001241:Aspirin / Q000737:chemistry*; D000068342:Aspirin, Dipyridamole Drug Combination; D002152:Calorimetry, Differential Scanning; D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations; D004176:Dipyridamole / Q000737:chemistry*; D004338:Drug Combinations; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D012995:Solubility; D013678:Technology, Pharmaceutical; D014961:X-Ray Diffraction
chemical_list: D000068342:Aspirin, Dipyridamole Drug Combination; D003692:Delayed-Action Preparations; D004338:Drug Combinations; D004176:Dipyridamole; D001241:Aspirin