Synthesis and in vivo studies of the radiosensitizer 4-[82Br]bromomisonidazole.

ABSTRACT

[82Br]Misonidazole ( [82Br]MISO) was investigated as a potential agent for scintillation imaging and indexing of hypoxic areas in tumor masses. [82Br]MISO was prepared by irradiating samples of Br-MISO in a SLOWPOKE reactor for 2 h at a thermal neutron flux of 10(12) n cm-2 s-1. Radiochemical yields ranged from 11 to 16%. [82Br]MISO had a plasma clearance half-life of approximately 40 min in BALB/c mice bearing EMT-6 tumors. The major metabolic product was identified as [82Br]Desmisonidazole. [82Br]MISO showed relatively high tumor uptake and persistently high plasma levels.