title: Development of controlled release osmotic pump tablet of glipizide solid dispersion.
abstract: OBJECTIVE
  To develop controlled release osmotic pump tablets (COPT) of glipizide (GZ) solid dispersion (SD).
  
  
  METHODS
  In elementary osmotic pump (EOP) tablets, an osmotic core with the drug is surrounded by a semi-permeable membrane which is drilled with a delivery orifice. COPT tablets eliminate the need of drilling process as controlled release can be achieved by the presence of osmogen in the coating. Poorly water soluble drug molecule cannot give satisfactory drug release hence GZ solid dispersion was prepared in the present study. The SDs having different ratio of drug to Poloxamer (PXM) 188 were prepared by hot melt method and optimized by solubility study, drug content estimation and in vitro dissolution study. Effect of two independent variables, amount of osmogen (potassium chloride) and hydrophilic polymer (polyethylene oxide WSR 303), were investigated using 3(2) factorial design. Core and coated tablets were evaluated for pharmacotechnical parameters. In-vitro drug release profiles of COPT tablets were compared with marketed with push-pull osmotic pump tablet, Glucotrol XL.
  
  
  RESULTS
  Prepared core and coated tablets showed acceptable pharmacotechnical parameters. Drug release was directly proportional to initial level of hydrophilic polymer, but inversely related to the osmogen, confirming osmotic mechanism. Zero order drug release pattern was achieved which was comparable to marketed product.
  
  
  CONCLUSIONS
  Novel oral controlled release of glipizide was successfully achieved by incorporating glipizide solid dispersion into osmotic system.
authors.forename: Gayatri C
authors.initials: GC
authors.lastname: Patel
authors.forename: Khushman V
authors.initials: KV
authors.lastname: Asodaria
authors.forename: Hetal P
authors.initials: HP
authors.lastname: Patel
authors.affiliation: Maliba Pharmacy College, Bardoli Mahuva Road, Dist. Surat, Gujarat 394 350, India. gayatripatel26@gmail.com.
authors.forename: Dinesh R
authors.initials: DR
authors.lastname: Shah
mesh_terms: D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics; D015195:Drug Design; D005913:Glipizide / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D009997:Osmotic Pressure; D020442:Poloxamer / Q000737:chemistry; D012995:Solubility; D013607:Tablets
chemical_list: D003692:Delayed-Action Preparations; D013607:Tablets; D020442:Poloxamer; D005913:Glipizide