title: [Studies on drug release from aminophylline konjac glucomannan matrix tablet].
abstract: OBJECTIVE
  In vitro aminophylline release from matrix tablets with konjac glucomannan (KGM) were studied to elevate the feasibility of KGM used as carrier materials to prepare matrix tablets.
  
  
  METHODS
  KGM hydrophilic matrix tablets were prepared by direct compression method with aminophylline as the model drug. The effects of test methods, pH values, ionic strength of dissolution media and rotation speeds on drug release were studied by in vitro dissolution experiment.
  
  
  RESULTS
  The MDT value tested by Paddle method was less than that tested by Basket method (P < 0.05). Among the rate of drug release in different dissolution media, distillded water is the fastest, pH 6. 8 PBS is the second, 0.1 mol x L(-1) HCL is the slowest. MDT increased with increasing the ionic strength of dissolution media (P < 0.05). MDT decreased with increasing the rotation speed, but the rate of drug release did not increase when the rotation speed was more than 100 r x min(-1) (P > 0.1). The mechanism of drug release were diffusion and erosion.
  
  
  CONCLUSIONS
  KGM can be used in sustained delivery systems as a good candidate of hydrophilic polymer.
authors.affiliation: Institute of Chinese Materia Medica, School of Pharmacy of Henan University, Kaifeng 475004, China.
authors.forename: Guang-Qiang
authors.initials: GQ
authors.lastname: Zhu
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Liu
mesh_terms: D000628:Aminophylline / Q000737:chemistry* / Q000493:pharmacokinetics; D031056:Amorphophallus / Q000737:chemistry; D001993:Bronchodilator Agents / Q000737:chemistry / Q000493:pharmacokinetics; D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations / Q000737:chemistry* / Q000493:pharmacokinetics; D004337:Drug Carriers; D006863:Hydrogen-Ion Concentration; D008351:Mannans / Q000737:chemistry*; D010946:Plants, Medicinal / Q000737:chemistry; D012995:Solubility; D013607:Tablets
chemical_list: D001993:Bronchodilator Agents; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D008351:Mannans; D013607:Tablets; D000628:Aminophylline; C022901:(1-6)-alpha-glucomannan