title: Pellet characteristics and drug release when the form of propranolol is fixed as moles or mass in formulations for extruded and spheronized Carbopol-containing pellets.
abstract: Characteristics of Carbopol-containing pellets have been shown to be dependent on the form of the weakly basic drug, propranolol, when the drug forms are fixed as masses in the formulations. To further investigate the effect of the drug forms on pellet and drug release characteristics, the drug forms were incorporated as a fixed number of moles in the formulation. Forms of propranolol, viz. the free base and the hydrochloride and maleate salt forms, resulted in different yield, roundness, smoothness, and friability, but the average pellet diameter was not affected. The free base form was released more slowly than the other two forms. Mathematical analysis of the release data revealed that Fickian diffusion and polymer relaxation contributed to the release mechanism in each case, although polymer relaxation was more influential with the free base form.
authors.affiliation: Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, University of the Sciences in Philadelphia, 600 S. 43rd Street, Philadelphia, PA 19104, USA.
authors.forename: Safak
authors.initials: S
authors.lastname: Paker-Leggs
authors.forename: Steven H
authors.initials: SH
authors.lastname: Neau
mesh_terms: D000179:Acrylates / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations; D004058:Diffusion; D004337:Drug Carriers / Q000737:chemistry*; D008962:Models, Theoretical; D010316:Particle Size; D011433:Propranolol / Q000737:chemistry*; D012492:Salts / Q000737:chemistry; D012995:Solubility; D013499:Surface Properties
chemical_list: D000179:Acrylates; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D012492:Salts; C117167:carbopol 974P NF; D011433:Propranolol