Microfluidic reactions using [11C]carbon monoxide solutions for the synthesis of a positron emission tomography radiotracer

• Published in: Organic & biomolecular chemistry 2011-05, Vol.9 (9), p.3313-3319
• Main Authors: Kealey, Steven, Plisson, Christophe, Collier, T Lee, Long, Nicholas J, Husbands, Stephen M, Martarello, Laurent, Gee, Antony D
• Format: Article
• Language: English
• Subjects: Carbon Monoxide - chemical synthesis; Carbon Radioisotopes - chemistry; Microfluidic Analytical Techniques; Microfluidics; Molecular Structure; Positron-Emission Tomography; Radioactive Tracers; Solutions - chemistry
• ISSN: 1477-0520; 1477-0539
• DOI: 10.1039/c0ob00631a

Microfluidic technology has been used to perform [(11)C]carbonylation reactions using solutions containing [(11)C]CO in the form of the complex, copper(i)tris(3,5-dimethylpyrazolyl)borate-[(11)C]carbonyl (Cu(Tp*)[(11)C]CO). The synthesis of the model compound [(11)C]N-benzylbenzamide and the known tracer molecule [(11)C]trans-N-[5-(2-flurophenyl)-2-pyrimidinyl]-3-oxospiro[5-azaisobenzofurane-1(3H),1'-cyclohexane]-4'-carboxamide ([(11)C]MK-0233), a ligand for the neuropeptide Y Y5 receptor, have been performed using this technique. Following semi-preparative HPLC purification and reformulation, 1262 ± 113 MBq of [(11)C]MK-0233 was produced at the end of the synthesis with a specific activity of 100 ± 30 GBq μmol(-1) and a >99% radiochemical purity. This corresponds to a decay corrected radiochemical yield of 7.2 ± 0.7%. Using a 3 mL vial as the reaction vessel, and following semi-preparative HPLC purification and reformulation, 1255 ± 392 MBq of [(11)C]MK-0233 was produced at the end of the synthesis with a specific activity of 100 ± 15 GBq μmol(-1) and a >99% radiochemical purity. This corresponds to a decay corrected radiochemical yield of 7.1 ± 2.2%.