cRGD, Flamma® 552 is an angiogenesis imaging fluorescent probe, made up of a covalent-connection of cyclic RGD with Flamma® 552. Cyclic RGD binds preferentially to αvβ3 integrin with high affinity. Integrin αvβ3 is known to strongly involve in the regulation of angiogenesis. The αvβ3 is generally expressed in low levels on the epithelial cells and mature endothelial cells, but it is highly expressed in many solid tumors. Cyclic RGD peptides are also able to bind αvβ5, α5β1, α6β4, α4β1, and αvβ6 integrins, which may help enhance their tumor uptake due to the increased receptor population. We offer cRGD, Flamma® 552 as in vivo fluorescent probes for imaging of blood vessels, tumors and angiogenesis.