Research Progress of Targeted Ultrasound Contrast Agent BR55 / 中国医学科学院学报

BR55 is an ultrasound contrast agent targeting vascular endothelial growth factor receptor 2,which can be used to detect tumor neovascularization and improve the diagnostic accuracy.Overseas researchers have used BR55 for human ultrasound molecular imaging,which showed good safety and tolerance.We reviewed the research progress on BR55 applied in the evaluation of tumor neovascularization from the composition,characteristics,animal experiments,and clinical studies of BR55.

Preparation and preliminary evaluation of KGDS-targeted ultrasound contrast agent / 中南大学学报(医学版)

Objective To prepare a thrombus-targeted ultrasonic contrast agent and to investigate its targeted ability to fresh blood clots. Methods We first synthesized FITC-KGDS-Palm compound, and then prepared thrombus-targeted microbubbles using "ultrasound & high speed shearing method".Fluorescence labeling thrombus-specific peptides and KGDS,directed at the activated glycoprotein(GP)Ⅱb/Ⅲa receptor of platelets were attached to the surface of lipid microbubbles. The concentration and size of TUCA were measured by Malvern Zeta Sizer Nano-ZS590 and Coulter counter.Immunofluorescence was applied to confirm the conjugation.The conjunct ratio was assessed by flow cytometer (FCM).Results The KGDS-TUCA was straw yellow turbid liquor,and the concentration was 1.5×10~9/mL,and the average size was 1.5 μm. The targeted microbubbles conjugated with the thrombus-specific peptides showed bright green rings by fluorescence microscope.FCM demonstrated that the wavelength of shell of KGDS-TUCA changed greatly,and the conjunct ratio was 90.04%.In vitro study showed KGDS-TUCA remained stable for 48 h at 4 ℃ and target-attached to blood clots and showed good stability.Conclusion The ultrasound & high speed shearing method to prepare TUCA is easy and in favor of purification.KGDS-TUCA has high specific biological activity.The conjunct ratio and stability of KGDS-TUCA are excellent.