title: Formulation and evaluation of gastroretentive floating drug delivery system of dipyridamole.
abstract: A multiple-unit floating alginate bead drug delivery system with prolonged stomach retention time was developed in this study. The floating alginate beads were prepared by ionic cross-linking method, using CaCO3 as the gas-forming agent. Over 92% of the beads remained floating after 9 h. In order to prepare sustained-release dosage forms of dipyridamole, the solid dispersion technique was applied using a blend of Eudragit L100 and Eudragit RLPO. Afterwards, the solid dispersions of dipyridamole were incorporated into the floating alginate beads. The drug release was modified by changing the ratio of Eudragit RLPO and Eudragit L100 in the solid dispersions. The in vivo results showed that the relative bioavailability of alginate beads was enhanced by approximately 2.52-fold compared with that of the commercial tablet. Therefore, our study illustrated the potential use of floating alginate beads combined with the solid dispersion technique for the delivery of acid-soluble compounds, such as dipyridamole.
authors.affiliation: Chongqing Key Laboratory of Biochemistry & Molecular Pharmacology, School of Pharmacy, Chongqing Medical University , Chongqing , China .
authors.forename: Huiming
authors.initials: H
authors.lastname: Jiang
authors.forename: Rui
authors.initials: R
authors.lastname: Tian
authors.forename: Wenjing
authors.initials: W
authors.lastname: Hu
authors.forename: Yuntao
authors.initials: Y
authors.lastname: Jia
authors.forename: Pei
authors.initials: P
authors.lastname: Yuan
authors.forename: Jiayu
authors.initials: J
authors.lastname: Wang
authors.forename: Liangke
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000464:Alginates / Q000737:chemistry; D000818:Animals; D017849:Animals, Inbred Strains; D001682:Biological Availability; D002152:Calorimetry, Differential Scanning; D055598:Chemical Phenomena; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics; D004176:Dipyridamole / Q000008:administration & dosage* / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics; D004285:Dogs; D004339:Drug Compounding; D016503:Drug Delivery Systems; D065546:Drug Liberation; D005079:Excipients / Q000737:chemistry*; D005750:Gastric Juice / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D010316:Particle Size; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage* / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics; D011109:Polymethacrylic Acids / Q000737:chemistry; D012995:Solubility
chemical_list: D000464:Alginates; D003692:Delayed-Action Preparations; D005079:Excipients; D006603:Hexuronic Acids; D010975:Platelet Aggregation Inhibitors; D011109:Polymethacrylic Acids; C038300:methylmethacrylate-methacrylic acid copolymer; D004176:Dipyridamole; D020723:Glucuronic Acid
keywords: Alginate; dipyridamole; floating beads; gastroretentive; solid dispersions