title: N-trimethyl chitosan-coated multivesicular liposomes for oxymatrine oral delivery.
abstract: BACKGROUND
  Multivesicular liposomes (MVLs), uncoated and coated with N-trimethyl chitosan (TMC), have been studied for their potential use for drug delivery by the oral route.
  
  
  METHODS
  Synthesized TMC was characterized by infrared spectroscopy, revealing the presence of trimethyl groups, and by proton nuclear magnetic resonance spectroscopy, allowing the calculation of the degree of substitution quaternization (70.2%). Oxymatrine (OM), a natural quinolizidine alkaloid used clinically for treating hepatitis B, was chosen as a model drug. The surface-modified MVLs and uncoated MVLs were characterized in vitro in terms of their shape, size, zeta potential, entrapment efficiency, coating efficiency, the stability of MVLs in polymer suspension, and the stability in simulated gastric and intestinal fluids.
  
  
  RESULTS
  In vivo, the area under the plasma concentration-time curve obtained from the pharmacokinetics study of TMC-coated MVLs was found to be about 3.26- and 1.96-fold higher than that of OM solution and uncoated MVLs, respectively.
  
  
  CONCLUSIONS
  TMC-coated MVLs can be considered as a potential carrier for oral drug administration.
authors.affiliation: Department of Pharmaceutical Sciences, Shenyang Pharmaceutical University, Shenyang, People's Republic of China.
authors.forename: Jinna
authors.initials: J
authors.lastname: Cao
authors.forename: Jukui
authors.initials: J
authors.lastname: Sun
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Wang
authors.forename: Xinran
authors.initials: X
authors.lastname: Li
authors.forename: Yingjie
authors.initials: Y
authors.lastname: Deng
mesh_terms: D000284:Administration, Oral; D000470:Alkaloids / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D000818:Animals; D000998:Antiviral Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D048271:Chitosan / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004339:Drug Compounding / Q000379:methods*; D004355:Drug Stability; D005260:Female; D005750:Gastric Juice / Q000737:chemistry; D006509:Hepatitis B / Q000188:drug therapy; D006863:Hydrogen-Ion Concentration; D007419:Intestinal Secretions / Q000737:chemistry; D008081:Liposomes; D008954:Models, Biological; D011807:Quinolizines / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D051381:Rats; D017208:Rats, Wistar; D000093842:Matrines
chemical_list: D000470:Alkaloids; D000998:Antiviral Agents; D048271:Chitosan; D008081:Liposomes; D011807:Quinolizines; C118071:N-trimethyl chitosan chloride; C037573:oxymatrine; D000093842:Matrines