title: Preparation of polyelectrolyte multilayer coated microbubbles for use as ultrasound contrast agent.
abstract: OBJECTIVE
  To prepare and characterize polyelectrolyte multilayer film coated microbubbles for use as ultrasound contrast agent (UCA) and evaluate its effects in ultrasonic imaging on normal rabbit's liver parenchyma.
  
  
  METHODS
  Perfluorocarbon (PFC)-containing microbubbles (ST68-PFC) were prepared by sonication based on surfactant (Span 60 and Tween 80). Subsequently, the resulting ST68-PFC microbubbles were coated using oppositely charged polyelectrolytes by microbubble-templated layer-by-layer self-assembly technique via electrostatic interaction. The enhancement effects in ultrasonic imaging on normal rabbit's liver parenchyma were assessed.
  
  
  RESULTS
  The obtained microbubbles exhibited a narrow size distribution. The polyelectrolytes were successfully assembled onto the surface of ST68-PFC microbubbles. In vivo experiment showed that polyelectrolyte multilayer film coated UCA effectively enhanced the imaging of rabbit's liver parenchyma.
  
  
  CONCLUSIONS
  The novel microbubbles UCA coated with polyelectrolyte multilayer, when enabled more function, has no obvious difference in enhancement effects compared with the pre-modified microbubbles. The polymers with chemically active groups (such as amino group and carboxyl group) can be used as the outermost layer for attachment of targeting ligands onto microbubbles, allowing selective targeting of the microbubbles to combine with desired sites.
authors.affiliation: Nanomedicine and Biosensor Laboratory, Bio-X Center, Harbin Institute of Technology, Harbin 150080.
authors.forename: Zhan-Wen
authors.initials: ZW
authors.lastname: Xing
authors.forename: Heng-Te
authors.initials: HT
authors.lastname: Ke
authors.forename: Shao-Qin
authors.initials: SQ
authors.lastname: Liu
authors.forename: Zhi-Fei
authors.initials: ZF
authors.lastname: Dail
authors.forename: Jin-Rui
authors.initials: JR
authors.lastname: Wang
authors.forename: Ji-Bin
authors.initials: JB
authors.lastname: Liu
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000737:chemistry*; D004573:Electrolytes / Q000737:chemistry*; D005466:Fluorocarbons / Q000737:chemistry; D008099:Liver / Q000000981:diagnostic imaging; D045423:Microbubbles; D011108:Polymers / Q000737:chemistry*; D011817:Rabbits; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry; D014465:Ultrasonics; D014463:Ultrasonography
chemical_list: D003287:Contrast Media; D004573:Electrolytes; D005466:Fluorocarbons; D011108:Polymers; D013501:Surface-Active Agents