Synthesis of n.c.a. [188, 189, 191pt] Cisplatin From a Cyclotron-produced n.c.a. 188, 189, 191PtCl42- Complex

Abstract

We developed a novel method for production of no-carrier-added (n.c.a.) [188, 189, 191Pt]PtⅡCl42- from an Ir target material, and then synthesized n.c.a. [*Pt]cis-[PtⅡCl2(NH3)2] ([*Pt]cisplatin) from [*Pt]PtⅡCl42-. [*Pt]PtⅡCl42- was prepared as a synthetic precursor of n.c.a. *Pt complex by a combination of resin extraction and anion-exchange chromatography after the selective reduction of IrⅣCl62- with ascorbic acid. The ligand-substitution reaction of Cl with NH3 was promoted by treating n.c.a. [*Pt]PtⅡCl42- with excess NH3 and heating the reaction mixture, and n.c.a [*Pt]cisplatin was successfully produced without employing precipitation routes. After this treatment, [*Pt]cisplatin was isolated through preparative HPLC with a radiochemical purity of 99+% at the end of synthesis (EOS).

Development of Novel 191Pt-Labeled Hoechst33258: 191Pt Is More Suitable than 111In for Targeting DNA

“…radio-cisplatin. 26,27 We found that radio-cisplatin causes severe DNA double-strand break (DSB) without chemical damage. 28 Unfortunately, the small DNA-binding fraction of radio-cisplatin led to a low probability of DSBs.…”