[68Ga]Ga-DO2A-(OBu-l-tyr)2: Synthesis, 68Ga-radiolabeling and in vitro studies of a novel 68Ga-DO2A-tyrosine conjugate as potential tumor tracer for PET

The synthesis, ⁶⁸Ga-labeling and in vitro study of the novel tyrosine chelate derivative ⁶⁸Ga]Ga-1,4,7,10-tetraazacyclododecane-1,7-diacetic acid-4,10-di-(O-butyl)-l-tyrosine (⁶⁸Ga]Ga-DO₂A-(OBu-l-tyr)₂) as a potential tracer for imaging tumor metabolism by positron emission tomography (PET) is presented. This approach combines the biological amino acid transporter targeting properties of l-tyrosine with the outstanding availability of ⁶⁸Ga^III via the ⁶⁸Ge/⁶⁸Ga generator. In vitro studies utilizing the F98-glioblastoma cell line revealed specific uptake of ⁶⁸Ga]Ga-DO2A-(OBu-l-tyr)₂ that was comparable to that of the reference O-(2-¹⁸F]fluoroethyl)-l-tyrosine (FET). These promising results indicate a high potential of ⁶⁸Ga]Ga-DO₂A-(OBu-l-tyr)₂ for molecular imaging of tumor-driven amino acid uptake by PET.