title: [Preparation of paeonol microemulsion gel its and transdermal characterization in vitro].
abstract: OBJECTIVE
  To prepare paeonol microemulsion and microemulsion gel, and investigate its content, physical and chemical properties. Their transdermal properties in vitro were studied as well.
  
  
  METHODS
  IPM acted as oil phase, lecithin/APG as surfactant, 1,2-propanediol as cosurfactant, water was added dropwise to the oil phase to prepare paeonol microemulsion at room temperature using magnetic stirring. HPLC method were used to determine the content of paeonol in paeonol microemulsion. Transmission electron microscopy and laser particle size analyzer were used to determine the shape and size of the microemulsion. Carbopol 940 was uesd as substrate to prepare paeonol microemulsion gel. Franz diffusion cell was used for characterizing the microemulsion and gel transdermal properties in vitro.
  
  
  RESULTS
  The paeonol microemulsion was O/W microemulsion. Its uniform particle size was 32 nm and was with roundness appearance and stable content. The steady-state permeation rates of paeonol saturated aqueous solution, microemulsion, and microemulsion gel were 47.846, 103.760, 70.401 microg x cm(-2) x h(-1), and their 12 h cumulative amount of infiltration were 657.179, 1 266.484, 881.217 microg x cm(-2), respectively.
  
  
  CONCLUSIONS
  The 12 h cumulative infiltration and infiltration rate of paeonol microemulsion and microemulsion gel are better than the saturated aqueous solution. Paeonol microemulsion gel is a new dosage form for transdermal drug delivery.
authors.affiliation: Department of Pharmacy, Changhai Hospital, Second Military Medical University, Shanghai 200433, China. liujiyong999@yahoo.com.cn
authors.forename: Jiyong
authors.initials: J
authors.lastname: Liu
authors.forename: Ying
authors.initials: Y
authors.lastname: Han
authors.forename: Ming
authors.initials: M
authors.lastname: Yang
authors.forename: Quangang
authors.initials: Q
authors.lastname: Zhu
authors.forename: Jinhong
authors.initials: J
authors.lastname: Hu
mesh_terms: D000098:Acetophenones / Q000493:pharmacokinetics*; D004337:Drug Carriers / Q000737:chemistry*; D016503:Drug Delivery Systems / Q000379:methods*; D004365:Drugs, Chinese Herbal / Q000493:pharmacokinetics*; D004655:Emulsions / Q000737:chemistry; D005782:Gels / Q000737:chemistry; D008954:Models, Biological; D012869:Skin Absorption
chemical_list: D000098:Acetophenones; D004337:Drug Carriers; D004365:Drugs, Chinese Herbal; D004655:Emulsions; D005782:Gels; C013638:paeonol