Synthesis and evaluation of a novel 68Ga-labeled DOTA-benzamide derivative for malignant melanoma imaging.

Malignant melanoma displays a highly aggressive metastasis. Thus, early diagnosis of malignant melanoma is important for patient survival. We designed and synthesized a novel (68)Ga-labeled benzamide derivative that specifically binds to melanoma as demonstrated by its ability to bind to melanin. (68)Ga-SCN-DOTA-PCA was synthesized with a radiochemical yield of ~80% and a radiochemical purity of >97% by analytical HPLC. The in vitro binding of (68)Ga-SCN-DOTA-PCA to melanin and its cellular uptake demonstrated the selective uptake in melanin. In addition, the biodistribution and micro-PET imaging of (68)Ga-SCN-DOTA-PCA in B16F10 tumor models showed the specific accumulation in melanoma. These results suggest that (68)Ga-SCN-DOTA-PCA would be a promising agent for melanoma diagnosis.