Radiosynthesis of [[103]Pd]-di-actyl-bis [N[4]-methylthio-semicarbazone]: a potential therapeutic agent

ABSTRACT

Due to interesting tumor imaging properties of bis-thiosemicarbazones, [[103]Pd]-di-acetylbis [N[4]-methylthiosemicarbazone] [[[103]Pd] ATSM[2]] was prepared according to the analogy of radio copper homologues. Palladium- 103 [T[1/2]=16.96 d] was produced via the [103]Rh [p,n] [103]Pd nuclear reaction with proton energy 18 MeV. The final activity was eluted in form of Pd [NH[4]][2]Cl[2] in order to react with bis-thiosemicarbazones to yield [[103]Pd]- labeled compounds. Chemical purity of the final product was confirmed to be below the accepted limits by polarography. The labeled compound was purified by reverse phase column chromatography using C[18] plus Sep-Pak. The partition co-efficient of the final complex was determined. The initial physico-chemical properties of the labeled compound was compared to those of their copper homologues. Radiochemical purity of more than 99% using RTLC was obtained [specific activity of about 12500-13000 Ci/mol]. The stability of the tracer was checked in final product and human serum, at 37[degree sing] C up to 48h. The labeled compound prepared in this study is probably one of the few new [103]Pd-radiolabeled compounds which have a potential for future biological studies, regarding its suitable physicochemical stability