PT  - JOURNAL ARTICLE
AU  - Zhou, Xingqin
AU  - Zhang, Jiankang
AU  - Xu, Xijie
AU  - Cao, Guoxian
AU  - Zhang, Rongjun
TI  - A preliminary study on a new memantine derivative [<sup>99m</sup>Tc]- N-3,5-dimethyltricyclo[3,3,1]decanyl-2-((2-mercaptoethyl)(2-(2-mercaptoethylamino)-2-oxoethyl)amino)acetamide
DP  - 2008 May 01
TA  - Journal of Nuclear Medicine
PG  - 310P--310P
VI  - 49
IP  - supplement 1
4099  - http://jnm.snmjournals.org/content/49/supplement_1/310P.3.short
4100  - http://jnm.snmjournals.org/content/49/supplement_1/310P.3.full
SO  - J Nucl Med2008 May 01; 49
AB  - 1319 Objectives: To develop a new technetium labeled ligand [99mTc]- N-3,5-dimethyltricyclo[3,3,1]decanyl-2-((2-mercaptoethyl)(2-(2-mercaptoethylamino)-2-oxoethyl)amino)acetamide (99mTc-NCAM) by using memantine coupled with N2S2 forming a stable complex as a potential SPECT imaging agent. Methods: The labeling precursor N-3,5-dimethyltricyclo[3,3,1]decanyl-2-((2-mercaptoethyl) (2-(2-mercaptoethylamino)-2-oxoethyl)amino)acetamide was synthesized in a four-step reaction sequence. The chemical structures of the labeling precursor and its intermediates were verified by IR,NMR and MS. A series of studies were performed to optimize labeling efficiency of 99mTc-NCAM.Radiochemical purity of 99mTc-NCAM was measured by HPLC. Biodistribution was studied in normal mice (n=36). Results: The octanol-water partition coefficient(logP)of 99mTc-NCAM was 2.0 determined by HPLC. The complex showed electrically neutral evaluated by electrophoresis, and its molecular weight was 413 daltons. 99mTc-NCAM was stable up to 6 h in aqueous solution and radiochemical purity was over 95% at selected condition. Biodistribution showed a fast clearance of radioactivity from blood. There was high brain uptake with increasing brain-blood ratios: 1.50, 4.95, 6.50, 6.87, 7.15 at 5, 30, 60, 120 ,240min, respectively. Conclusions: These results indicate that 99mTc –NCAM are favorable for transport through the BBB. It is probably a potential SPECT imaging agent and further study is needed. Research Support: Project supported by National Natural Science Foundation of China (30770602), Key Project supported by Medical Science and Technology Development Foundation, Jiangsu Province Department of Health (K200512).