title: Evaluation and optimization of preparative variables for controlled-release floatable microspheres prepared by poor solvent addition method.
abstract: The aim of this study was to evaluate and optimize preparative parameters for floatable theophylline microspheres prepared by the emulsion-solvent evaporation method. A three-factor three-level Box-Behnken design was employed using amount of poor solvent, temperature-increase rate and drug loading as independent factors, and percentage floating at 3 h and time required for 50% drug release as dependent variables. Simultaneous optimization of the parameters for maximum buoyancy and desirable drug release was conducted using a partitioned artificial neural network. A microsphere using 27.6% of drug loading, 0.29 degrees C/min of temperature-increase rate, and 1.7 mL of poor solvent was identified for maximizing buoyancy and sustaining drug release.
authors: Department of Pharmacy, Tokyo Women's Medical University Medical Center East, Nishiogu, Arakawa-ku, Tokyo, Japan. myph@dnh.twmu.ac.jp
authors: Yasunori
authors: Y
authors: Miyazaki
authors: Shigeru
authors: S
authors: Yakou
authors: Fumiki
authors: F
authors: Yanagawa
authors: Kozo
authors: K
authors: Takayama
mesh_terms: D002626:Chemistry, Pharmaceutical / Q000379:methods*; D003692:Delayed-Action Preparations / Q000737:chemistry* / Q000493:pharmacokinetics; D004353:Drug Evaluation, Preclinical / Q000379:methods; D008863:Microspheres; D010316:Particle Size; D012997:Solvents / Q000737:chemistry* / Q000493:pharmacokinetics
chemical_list: D003692:Delayed-Action Preparations; D012997:Solvents