Targestar SA

Targestar SA is a microsphere contrast agent coated with streptavidin for easy 1-step conjugation of biotinylated ligands

  • Accumulated MAdCAM-1 targeted MB in mouse model of Crohn's Disease

  • MAdCAM-1-targeted microbubbles accumulation in mouse model of inflammatory bowel disease (120 X Speed)

  • Negligable retention of control-targeted microbubbles in mouse model of inflammatory bowel disease

  • VEGFR2-targeted microbubbles in subcutaneous melanoma, 40 MHz

Applications

Targestar SA is a perfluorocarbon microsphere encapsulated with a lipid shell coated with streptavidin conjugated to the distal tip of a polymeric spacer. Biotinylated antibodies can be easily conjugated to the microsphere surface, enabling target-specific retention of the microsphere for molecular imaging. Because the micron-scale size (mean diameter 2.5 um) of the microsphere prevents extravasation, molecular targets must be expressed on the luminal vascular endothelium. Targeson has validated several molecular targets for imaging angiogenesis, inflammation, and thrombosis.

Directions for Use

Targestar SA is a microsphere ultrasound contrast agent that is coated with streptavidin. Biotinylated ligands, such as peptides, antibodies, and glycoconjugates, can be bound to the surface of the agents using biotin-streptavidin conjugation chemistry. After ligand conjugation, Targestar SA is stable for up to 8 hours when stored at 4-8 degrees C. Excess biotinylated ligand that is not bound to the surface of the microbubbles may interfere with targeted microbubble adhesion in vivo; excess ligand can be removed from the preparation by centrifugal washing using the provided kit.

Specifications

Targestar SA can be used for ultrasound contrast imaging of any molecular marker on the endothelium. Biotinylated targeting ligands (supplied by user) can be conjugated to Targestar SA via streptavidin on the agent surface. The agent echogenicity is optimal at ultrasound frequencies in 1-20 MHz range, and ultra-high frequency imaging (20-40 MHz) is also possible. Contrast imaging settings such as pulse inversion or CPS must be enabled on the ultrasound scanner for optimal contrast sensitivity. The agent remains acoustically active for 5-15 minutes, depending on the administered dose. Optimal dosages vary with application. Targestar SA has been used successfully with targeting ligands such as MADCAM, VEGFR2, P Selectin, VCAM, E Selectin, as well as others.