Design and synthesis of tumor-targeting theranostic drug conjugates for SPECT and PET imaging studies.

Theranostics will play a significant role in the next-generation chemotherapy. Two novel tumor-targeting theranostic drug conjugates, bearing imaging arms, were designed and synthesized. These theranostic conjugates consist of biotin as the tumor-targeting moiety, a second generation taxoid, SB-T-1214, as a potent anticancer drug, and two different imaging arms for capturing 99mTc for SPECT (single photon emission computed tomography) and 64Cu for PET (positron emission tomography). To explore the best reaction conditions for capturing radionuclides and work out the chemistry directly applicable to "hot" nuclides, cold chemistry was investigated to capture 185Re(I) and 63Cu(II) species as surrogates for 99mTc and 64Cu, respectively.