title: Production of spherical pellets by a hot-melt extrusion and spheronization process.
abstract: Controlled-release theophylline containing spherical pellets were successfully produced by a hot-melt extrusion (HME) and spheronization process. A powder blend of anhydrous theophylline, Eudragit Preparation 4135 F, microcrystalline cellulose and polyethylene glycol 8000 powder was sieved, blended and then melt-extruded in a Randcastle Microtruder. The hot-melt extruded pellets were prepared by first cutting a thin, extruded composite rod into symmetrical pellets. The pellets were then spheronized in a traditional spheronizer at an elevated temperature. Thermal properties of the pellet formulation components and the hot-melt extrudate were studied to determine suitability of the formulation for HME. Pellets were examined using scanning electron microscopy to determine the effect of spheronization time on surface morphology. The rate of release of theophylline from the hot-melt extruded spherical pellets was characterized using USP 24 Apparatus 2 dissolution testing after initial pellet production and after 1 year storage in sealed HDPE containers at 25 degrees C/60% RH.
authors.affiliation: Drug Dynamics Institute, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA. chris.young@mail.utexas.edu
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Young
authors.forename: John J
authors.initials: JJ
authors.lastname: Koleng
authors.forename: James W
authors.initials: JW
authors.lastname: McGinity
mesh_terms: D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000737:chemistry; D003692:Delayed-Action Preparations; D004055:Differential Thermal Analysis; D004339:Drug Compounding / Q000379:methods*; D004355:Drug Stability; D005079:Excipients; D008689:Methacrylates; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010316:Particle Size; D011109:Polymethacrylic Acids; D011208:Powders; D012995:Solubility; D013806:Theophylline / Q000008:administration & dosage / Q000737:chemistry; D013997:Time Factors
chemical_list: D001993:Bronchodilator Agents; D003692:Delayed-Action Preparations; D005079:Excipients; D008689:Methacrylates; D011109:Polymethacrylic Acids; D011208:Powders; C038300:methylmethacrylate-methacrylic acid copolymer; D013806:Theophylline