| NUKLEONIKA 2008, 53(3):97-101
NEW MICROWAVE ASSISTED RADIOLABELLING METHOD AND RAT BRAIN BIODISTRIBUTION STUDY OF TWO NEW 99mTc-TRICARBONYL COMPLEXES AS POTENTIAL BRAIN IMAGING AGENTSMoez Trabelsi1, Abdelkader Mekni2, Chandra Solanki3, Paul Maltby1, Mouldi Saidi2 1 Radiopharmacy Department, Royal Liverpool University Hospital, Prescot Str., Liverpool, L7 8XP England, UK 2 Centre National des Sciences et Technologies Nucléaires, 2020 Sidi Thabet, Tunisia 3 Department of Nuclear Medicine, Addenbrookes Hospital, Hills Road, P. O. Box 170, Cambridge CB2 2QQ, England, UK Two new cyclopentadienyl piperidine derivatives, namely ferrocene carboxylic acid 1-ethyl-3-hydroxypiperidinyl ester and ferrocene carboxylic acid 4-hydroxypiperidinyl ester, were synthesized. The ligands were then radiolabelled with 99mTc using two different approaches. The first method consisted of reacting the ligand precursor with Mn(CO)5Br in pertechnetate 99mTcO4– in normal saline and dimethyl formamide (DMF) at 150°C for 1 h. The yields were 70% and 90%, respectively. For the second method, the reactions mixtures were placed in a microwave oven for 2 min at 650 watt. The yields were higher than 90% for both 99mTc complexes. Biodistribution studies showed that tricarbonyl{eta5-[carboxy-3-hydroxy(N-ethyl)piperidine]cyclopentadienyl}technetium(I) had the highest brain uptake. The regional distribution in the brain also demonstrated relatively higher uptake of tricarbonyl{eta5-[carboxy-3-hydroxy(N-ethyl)piperidine]cyclopentadienyl}technetium(I) in the colliculus (1.97% ID/g tissue,) with the colliculus to cerebellum ratio of 1.99. We conclude that the radiolabelling can be achieved by microwave activation, and tricarbonyl{eta5-[carboxy-3-hydroxy(N-ethyl)piperidine]cyclopentadienyl}technetium(I) has the potential for use as central nervous system (CNS) imaging agent. Close X |