Preparation and Bioevaluation of DOTA-Cyclic RGD Peptide Dimer Labeled with 68Ga

Radiolabeled cyclic RGD peptides targeting integrin αvβ3 are reported as promising agents for the early diagnosis of metastatic tumors. With an aim to improve tumor uptake and retention of the peptide, cyclic RGD peptide dimer E[c (RGDfK)] 2 (E = Glutamic acid, f = phenyl alanine, K = lysine) coupled to the bifunctional chelator DOTA was custom synthesized and radiolabelled with 68Ga. Radiolabelling of cyclic RGD peptide dimer with 68Ga was carried out using HEPES buffer and biological evaluation of the complex was done in nude mice bearing HT29 tumors.

• Archana Mukherjee
• Aruna Korde
• Sudipta Chakraborty
• H. D. Sarma
• Grace Samuel
• M. R. A. Pillai

• 68Ga peptides
• Angiogenesis imaging
• Cyclic RGD peptides
• PET Imaging.

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