title: Experiment on formulation and drug release behavior of porosity asymmetric membrane capsules in vitro.
abstract: Porosity asymmetric membrane capsules were prepared to study the relationship between the capsule formulation and drug release. Cellulose acetate (CA) and pore formers were used in the capsule shell formulation as the main semipermeable membrane material. The capsules were permeable to both water and dissolved solutes. Using sparingly soluble drug acetaminophen as a model, cumulative release was calculated. The slope of the release profile from the distilled water had good relationship with the concentration of the pore formers F68. The release of acetaminophen was independent to the pH, osmotic pressure of dissolution medium, but influenced by intensity of agitation. When the concentration of pore former was low, zero-order release behavior was observed within 24 h which was consistent with Fickian diffusion model. When the concentration of pore former was high, however, Higuchi model release was found which is caused by Fickian diffusion and osmotic pressure release. With scanning electron microscope (SEM), the surface structure and cross-section of the capsule shell were also studied before and after drug delivery. With simple preparation and broad scope of drug application, porosity asymmetric membrane capsules can give desired drug extended release and show more convenience than controlled tablets with laser drilling.
authors.affiliation: School of Pharmacy, Wenzhou Medical College, Wenzhou, China.
authors.forename: Hong-Xing
authors.initials: HX
authors.lastname: Fu
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Fu-Zhi
authors.initials: FZ
authors.lastname: Zhang
authors.forename: Ying-Zheng
authors.initials: YZ
authors.lastname: Zhao
authors.forename: Chang-Wei
authors.initials: CW
authors.lastname: Wan
authors.forename: Mi-Te
authors.initials: MT
authors.lastname: Chen
authors.forename: Xue-Chao
authors.initials: XC
authors.lastname: Jia
authors.forename: Li
authors.initials: L
authors.lastname: Yan
authors.forename: Chuan-Chuan
authors.initials: CC
authors.lastname: Sun
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Xu
mesh_terms: D000082:Acetaminophen / Q000493:pharmacokinetics*; D018712:Analgesics, Non-Narcotic / Q000493:pharmacokinetics*; D002214:Capsules / Q000737:chemistry*; D002482:Cellulose / Q000031:analogs & derivatives* / Q000737:chemistry; D003692:Delayed-Action Preparations; D004058:Diffusion; D016503:Drug Delivery Systems; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D008962:Models, Theoretical; D009995:Osmosis; D016062:Porosity; D012995:Solubility
chemical_list: D018712:Analgesics, Non-Narcotic; D002214:Capsules; D003692:Delayed-Action Preparations; D000082:Acetaminophen; C005062:acetylcellulose; D002482:Cellulose