Effect of molecular weight, crystallinity, and hydrophobicity on the acoustic activation of polymer-shelled ultrasound contrast agents

Ceciel Chlon, Constant Guédon, Bram Verhaagen, William T. Shi, Christopher S. Hall, Johan Lub, Marcel R. Böhmer

Research output: Contribution to journalArticleAcademicpeer-review

25 Citations (Scopus)

Abstract

Polymer-shelled microbubbles are applied as ultrasound contrast agents. To investigate the effect of the polymer on microbubble preparation and acoustic properties, polylactides with systematic variations in molecular weight, crystallinity, and end-group hydrophobicity were used. Polymer-shelled cyclodecane filled capsules were prepared by emulsification, and the cyclodecane was removed by lyophilization to obtain hollow capsules. Complete removal of cyclodecane from the microcapsules was only achieved for short chain (about Mw 6000) crystalline polymers. The pressure threshold for acoustic destruction of the microbubbles was found to increase with molecular weight. Noncrystalline polymers showed a higher threshold for destruction than crystalline polymers. Hydrophobically modified short chain crystalline polymers showed the steepest increase in acoustic destruction after the threshold as a function of the applied pressure, which is a favorable characteristic for ultrasound mediated drug delivery. Microcapsules made with such polymers had an inhomogeneous surface including pores through which cyclodecane was lyophilized efficiently.

Original languageEnglish
Pages (from-to)1025-1031
Number of pages7
JournalBiomacromolecules
Volume10
Issue number5
DOIs
Publication statusPublished - 11 May 2009
Externally publishedYes

Fingerprint Dive into the research topics of 'Effect of molecular weight, crystallinity, and hydrophobicity on the acoustic activation of polymer-shelled ultrasound contrast agents'. Together they form a unique fingerprint.

  • Cite this