title: [Preparation of lung targeting azithromycin liposomes and its tissue distribution in mice].
abstract: OBJECTIVE
  To prepare lung targeting azithromycin cationic liposomes and to observe its tissue distribution in mice.
  
  
  METHODS
  The azithromycin cationic liposomes were prepared by thin film method with freeze-thawing steps. HPLC method was established and validated for the determination of azithromycin in tissues of mice.
  
  
  RESULTS
  The particle size of the liposomes was 6.582 microm with zeta potential of +19.5 mV. The entrapment efficiency was more than 75%. The liposomes was stable in 6 months stored at 4 degrees C. The release in vitro was characterized by Higuchi equation. Azithromycin liposomes and free azithromycin solution were injected intravenously at a dose of 80 mg x kg(-1) to mice. Compared with solution, liposomes were characterized by slower clearance, increased half-life and the AUC increased by 7.4 fold in lung.
  
  
  CONCLUSIONS
  Thin film method with freeze-thawing steps could increase the entrapment efficiency and increase the particle size of azithromycin liposomes. After modification of lipid membrane with stearylamine, the cationic liposomes were prepared. The azithromycin concentration and AUC increased in lung after iv administration to mice of the cationic liposomes. This offered a good information for preparing liposomes targeting on the lung.
authors.affiliation: Institute of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, China. wjiansong@hotmail.com
authors.forename: Jian-song
authors.initials: JS
authors.lastname: Wang
authors.forename: Jia-bi
authors.initials: JB
authors.lastname: Zhu
authors.forename: Rui-qin
authors.initials: RQ
authors.lastname: Lu
authors.forename: Wei
authors.initials: W
authors.lastname: Shen
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D019540:Area Under Curve; D017963:Azithromycin / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D002412:Cations; D004337:Drug Carriers; D004339:Drug Compounding / Q000379:methods; D016503:Drug Delivery Systems; D005260:Female; D008081:Liposomes; D008168:Lung / Q000378:metabolism*; D008297:Male; D051379:Mice; D010316:Particle Size; D014018:Tissue Distribution
chemical_list: D000900:Anti-Bacterial Agents; D002412:Cations; D004337:Drug Carriers; D008081:Liposomes; D017963:Azithromycin