Abstract
Developing CXCR4 receptor imaging agents is of great importance for oncological imaging. In this work, N, N´-[1, 4-Phenylenebis(methylene)]bis-1,4,8,11-tetraazacyclotetradecane was labeled using high purity [111In]InCl3 in 30- 60 min at 60°C in acetate buffer with acceptable yield and radiochemical purity (>97% ITLC, >95% HPLC, specific activity: 120-200 GBq/mmol). Radiolabeled complex of AMD-3100 ([111In]-AMD3100) showed good stability at room temperature and physiologic conditions in human serum for 24 h. Log P for the complex was determined (-1.18) to be consistent with a water soluble/ionic complex.
The biodistribution of the radiolabeled complex of plerixafor in vital organs of rats was determined up to 48 h demonstrating kidneys as the major route of excretion. Considering lungs, spleen and liver as the CXCR4 rich target organs, the best target:non target ratios (for spleen:blood, lung:blood and liver:blood) were obtained 24 h post injection (5.11, 2.08 and 10.63 respectively).
Keywords: AMD3100, biodistribution, CXCR4, In-111, plerixafor, radiolabeling.
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