Handbook of Biomedical Optics

Molecular Reporter Systems for Optical Imaging 683

that promotes angiogenesis through binding to its specic

receptor, VEGFR. VEGF protein was conjugated to Qdots along

with the metal chelator, 1,4,7,10-tetraazacyclododecane-1,4,7,10-

tetraacetic acid (DOTA) for Cu-64 for PET imaging of VEGFR

expression in glioblastoma xenogras (Chen et al. 2008). A

single-chain VEGF with a cysteine tag was labeled with a NIR

uorescent for detection of angiogenesis in tumors in mice

(Backer et al. 2007, Wang et al. 2009).

Other natural protein receptor ligands have been labeled

with uorescent tags for in vitro and in vivo imaging of recep-

tor expression. ese include transferring (Becker et al. 2000b),

vasoactive intestinal p