| abstract |
Provided are a retro-inverso polypeptides, DA7R, and a head-to-tail cyclized polypeptides with an amide bond, cA7R, having a high binding activity with vascular endothelial growth factor receptor-2 and neuropilin-1, and said polypeptides have an anti-tumor effect. Also provided are a composite of the polypeptides with a fluorescein, a drug, or a polymer carrier material, a preparation method thereof, and a use thereof in tumor imaging and targeted therapeutic drug delivery system construction. |