Effects of the liposomal formulation on the behavior and physical characteristics of acoustic liposomes

Nicolas Sax, Sachiko Horie, Li Li, Maya Sakamoto, Shiro Mori, Tetsuya Kodama

Research output: Chapter in Book/Report/Conference proceedingConference contribution


Ultrasound contrast agents (UCAs) are nano/microbubbles that contain air or a highmolecular-weight, low-solubility gas encapsulated in a lipid or albumin shell. Previous studies have developed acoustic liposomes (ALs), liposomes that encapsulate perfluoropropane (C3F8) gas. These ALs can be used as just UCAs, for early diagnostic or observation of angiogenesis. They can alsobe used for drug delivery, through their ultrasound-induced destruction leading to permeabilization of the neighboring cells. However, the echogenicity of ALs decreases within minutes, raising the need for more stable preparations. Here we show that the in vitro stability of ALs is affected by fluiditychanges in the bilayer, the presence of anionic phospholipids and the density of the PEG coating layer. These results allowed the preparation of "optimized" ALs displaying a 50% enhanced detection time in vitro. We anticipate their stability to be enhanced in a similar manner, in vivo. Further researchaims at further improvement of the stability of gas encapsulation by surface modification and coatingof the liposomes, and in vivo characterization of the optimized ALs.

Original languageEnglish
Title of host publicationNonlinear Acoustics
Subtitle of host publicationState-of-the-Art and Perspectives, ISNA 2012 - 19th International Symposium on Nonlinear Acoustics
Number of pages4
Publication statusPublished - 2012 May

Publication series

NameAIP Conference Proceedings
ISSN (Print)0094-243X
ISSN (Electronic)1551-7616


  • Contrast agent
  • Liposome
  • Microbubbles
  • PEG
  • Ultrasound imaging

ASJC Scopus subject areas

  • Physics and Astronomy(all)


Dive into the research topics of 'Effects of the liposomal formulation on the behavior and physical characteristics of acoustic liposomes'. Together they form a unique fingerprint.

Cite this