More importantly, the F3 peptide labeled with radioactive 68Ga could successfully detect GPC-3-positive HCC tumors in vivo and the PET imaging analysis revealed a high uptake of tumor compared to the minor background accumulation (4.50 ± 1.20 to 0.27 ± 0.14% ID/g). Here, GPC3 is linked to hepatocellular carcinoma.