Fully Automated One-pot Synthesis of [18F]fluoromisonidazole

A (18)F-labeled fluoromisonidazole (1H-1-(3-[(18)F]fluoro-2-hydroxypropyl)-2-nitroimidazole, [(18)F]FMISO) was prepared via a one-pot, two-step synthesis procedure using a modified commercial Tracerlab FX(F-N) synthesis module. Nucleophilic fluorination of the precursor molecule 1-(2'-nitro-1'-imidazolyl)-2-O-tetrahydropyranyl-3-O-toluenesulphonylpropanediol using no-carrier-added [(18)F]fluoride, followed by hydrolysis of the protecting group with 1 mol/L HCl and purification with Sep-Paks instead of HPLC, gave [(18)F]FMISO. The overall radiochemical yield with no decay correction was greater than 40%, the whole synthesis time was less than 40 min and the radiochemical purity was greater than 95%. The new automated synthesis procedure can be applied to the fully automated synthesis of [(18)F]FMISO using a commercial FDG synthesis module.