Pharmacodynamics of streptavidin-coated cyanoacrylate microbubbles designed for molecular ultrasound imaging

Invest Radiol. 2008 Mar;43(3):162-9. doi: 10.1097/RLI.0b013e31815a251b.


Objectives: To assess the pharmacodynamic behavior of cyanoacrylate, streptavidin-coated microbubbles (MBs) and to investigate their suitability for molecular ultrasound imaging.

Materials and methods: Biodistribution of MBs was analyzed in tumor-bearing mice using gamma-counting, immunohistochemistry, flow cytometry, and ultrasound. Further, vascular endothelial growth factor receptor 2-antibody coupled MBs were used to image tumor neovasculature.

Results: After 1 minute >90% of MBs were cleared from the blood and pooled in the lungs, liver, and spleen. Subsequently, within 1 hour a decent reincrease of MB-concentration was observed in the blood. The remaining MBs were removed by liver and spleen macrophages. About 30% of the phagocytosed MBs were intact after 48 hours. Shell fragments were found in the kidneys only. No relevant MB-accumulation was observed in tumors. In contrast, vascular endothelial growth factor receptor 2-specific MBs accumulated significantly within the tumor vasculature (P < 0.05).

Conclusions: The pharmacokinetic behavior of streptavidin-coated cyanoacrylate MBs has been studied. In this context, the low amount of MBs in tumors after >5 minutes is beneficial for specific targeting of angiogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carcinoma, Squamous Cell / diagnostic imaging*
  • Carcinoma, Squamous Cell / metabolism*
  • Coated Materials, Biocompatible / chemistry
  • Contrast Media / pharmacokinetics*
  • Cyanoacrylates / chemistry*
  • Metabolic Clearance Rate
  • Mice
  • Mice, Nude
  • Microbubbles*
  • Organ Specificity
  • Streptavidin / chemistry
  • Streptavidin / pharmacokinetics*
  • Tissue Distribution
  • Ultrasonography


  • Coated Materials, Biocompatible
  • Contrast Media
  • Cyanoacrylates
  • Streptavidin