title: Ammonio polymethacrylate-coated diltiazem: drug release from single pellets, media dependence, and swelling behavior.
abstract: Drug release from single pellets was measured on an easily assembled flow-through system. Despite heterogeneity between pellets, the sum of the individual results resembled drug release from an ensemble. A typical pellet displayed a long lag followed by rapid release. Heterogeneity appeared to result from substrate properties rather than coating uniformity. Swelling behavior in acid and buffer was measured by dynamic image analysis and related to drug release. Drug release was sensitive to dissolution temperature but swelling was not. A description of the drug release process was proposed.
authors.affiliation: Formulation Development, Actavis Elizabeth LLC, Elizabeth, NJ 07207, USA. gheinicke@actavis.com
authors.forename: Grant
authors.initials: G
authors.lastname: Heinicke
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Schwartz
mesh_terms: D002121:Calcium Channel Blockers / Q000737:chemistry*; D004110:Diltiazem / Q000737:chemistry*; D004343:Drug Implants; D010316:Particle Size; D011109:Polymethacrylic Acids / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D013997:Time Factors
chemical_list: D002121:Calcium Channel Blockers; D004343:Drug Implants; D011109:Polymethacrylic Acids; D000644:Quaternary Ammonium Compounds; C030613:polymethacrylic acid; D004110:Diltiazem