PSMA-D5 has a binding affinity for PSMA with K i of 0.21 nM and can be used for PSMA tracing after radiolabeling. PSMA-D5 ([ 68 Ga]-labeled) contains a DOTA chelator, allowing convenient labeling with therapeutic radionuclides such as 177 Lu and 225 Ac. PSMA-D5 ([ 68 Ga]-labeled) shows excellent pharmacokinetic properties, exhibiting remarkable tumor uptake in 22Rv1 tumors. PSMA-D5 can be used for the synthesis/research of Radionuclide-Drug Conjugates (RDCs).