SUCCESSIVE PREPARATION OF C-11 LABELED SODIUM-ACETATE AND/OR SODIUM HEXANOATE

A system for two-lot delivery of [l-C-11]acetate and/or [l-C-11]hexanoate using an automated synthesis unit for C-11-methylation with [C-11]methyl iodide is described. Carboxylation of methylmagnesium bromide and pentyl-magnesium bromide with [C-11]CO2 followed by HCl by drolysis gave [l-C-11]acetic acid and [I-C-11]hexanoic acid, respectively. The reaction mixture was passed through a Sep-IC-Ag cartridge, and the eluate was added to a NaHCO3 solution. After removing radioactive and non radioactive undesirable materials by evaporation of the solution to dryness, the residue was dissolved in physiological saline. By membrane filtration, a sterile and apyrogenic solution of [l-C-11]acetic acid or medium-chain fatty acids such as [l-C-11]hexanoic acid was ready for injection within 15 min of EOB. The reaction was successively carried out using two reaction sites in the system.