title: [Studies of in vitro releasing properties on cyclovirobuxine D matrix-type patch].
abstract: OBJECTIVE
  To study the drug releasing properties of Cyclovirobuxine D matrix-type patch.
  
  
  METHODS
  To prepare Cyclovirobuxine D single-layered and double-layered patch was prepared and the study the drug releasing properties by in vitro releasing and in vitro skin permeation experiments was studied.
  
  
  RESULTS
  The coefficient of first-order dynamical equation was good for single-layered patch, which means the releasing rate decreased with the amounts of drug decreasing. Nevertheless, Higuchi equation was good for double-layered patch, which means it belonged framing-type releasing system. In-vitro skin permeation experiment showed that zero-order dynamical equation was good for these two patches which indicated all of them abided by Ficks diffusion law.
  
  
  CONCLUSIONS
  The structure of patch can change the drug releasing properties, the double-layered patch can obtain steady releasing and permeating rate because of storage layer releasing.
authors.affiliation: Department of Pharmaceutics, Guangzhou of Traditional Chinese Medicine, Guangzhou 510006, China. yuyang@gzhtcm.edu.cn
authors.forename: Yang
authors.initials: Y
authors.lastname: Yu
authors.forename: Liling
authors.initials: L
authors.lastname: Zhou
authors.forename: Xiumei
authors.initials: X
authors.lastname: Li
mesh_terms: D000279:Administration, Cutaneous; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage* / Q000378:metabolism / Q000493:pharmacokinetics; D008954:Models, Biological; D010539:Permeability; D012867:Skin / Q000378:metabolism*
chemical_list: D004365:Drugs, Chinese Herbal; C032939:cyclovirobuxine D