title: Development of sustained release matrix tablets of didanosine containing methacrylic and ethylcellulose polymers.
abstract: Didanosine, a nucleoside analog used in the treatment of acquired immuno deficiency syndrome (AIDS), has been incorporated into directly compressed monolythic matrices whose excipients were mixtures at different ratios of a methacrylic resin (Eudragit RSPM) and an ethylcellulose (Ethocel 100), both water-insoluble and pH-independent polymers. Technological characterization (drug particle morphology, mean weight, diameter, thickness and hardness of tablets) was carried out and in vitro drug release behaviour was measured using the USP basket apparatus. The effect of varying the Eudragit-Ethocel ratio, as well as the drug-polymeric matrix ratio, was evaluated. The results showed the suitability of Eudragit-Ethocel mixtures as matrix-forming material for didanosine sustained release formulations. Combination of the moderate swelling properties of Eudragit RSPM with the plastic properties of the more hydrophobic Ethocel 100 allowed suitable modulation of didanosine release.
authors.affiliation: Departamento de Farmacia y Tecnología Farmacéutica, Sevilla, Spain.
authors.forename: Carla
authors.initials: C
authors.lastname: Sánchez-Lafuente
authors.forename: M
authors.initials: M
authors.lastname: Teresa Faucci
authors.forename: Mercedes
authors.initials: M
authors.lastname: Fernández-Arévalo
authors.forename: Josefa
authors.initials: J
authors.lastname: Alvarez-Fuentes
authors.forename: Antonio M
authors.initials: AM
authors.lastname: Rabasco
authors.forename: Paola
authors.initials: P
authors.lastname: Mura
mesh_terms: D019380:Anti-HIV Agents / Q000008:administration & dosage* / Q000737:chemistry; D002482:Cellulose / Q000031:analogs & derivatives; D002851:Chromatography, High Pressure Liquid; D003692:Delayed-Action Preparations; D016049:Didanosine / Q000008:administration & dosage* / Q000737:chemistry; D006244:Hardness; D006863:Hydrogen-Ion Concentration; D007091:Image Processing, Computer-Assisted; D008689:Methacrylates; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D011108:Polymers
chemical_list: D019380:Anti-HIV Agents; D003692:Delayed-Action Preparations; D008689:Methacrylates; D011108:Polymers; C008384:methacrylic acid; C013517:ethyl cellulose; D002482:Cellulose; D016049:Didanosine