Objective:

To evaluate the targeting ability of vascular endothelial growth factor receptor 2 (VEGFR2)-targeted microbubbles to tumor cells and its preparation process.

Methods:

VEGFR2-targeted microbubbles were accomplished by biotinavidin linkage of VEGFR2 antibody and USphere ultrasonic contrast agent. The features were detected by dynamic light scattering (DLS) and laser scanning confocal microscope (LSCM). The VEGFR2 expression intensities in MHCC-97H cells (high metastatic human

hepatic carcinoma cells) and LO2 cells (human liver cells) were compared by immunofluorescence method. The combination rates of VEGFR2-targeted microbubbles and non-targeted micro bubbles with both cell lines were documented by quantitative immunofluorescence technique.

Results:

VEGFR2-targeted microbubbles were distributed evenly with average particle size of (1 012.6778.59) nm. Immunofluorescence assay showed green fluorescence visible on the surface of the targeted micro bubbles. The immunofluorescence signal was higher in MHCC-97H cells than that in LO2 cells. The fluorescence signal ratio of VEGFR2-targeted microbubbles was (0.750.32) in MHCC-97H cells

which was significantly higher than that in other three groups (

P

0.01).

Conclusion:

VEGFR2-targeted microbubbles with a stable average size are successfully prepared. The micro bubbles could specifically combind with VEGFR2-high-expressing MHCC-97H cells.