Optimization of labeling conditions and bioevalution of 99m Tc-Meloxicam for inflammation imaging

Labeling of Meloxicam with 99mTc was done by direct addition of pertechnetate in isotonic solution to Sn-Meloxicam solution. High labeling yield (98%) was attained in 30 min at room temperature. The effect of various factors on the labeling yield was studied. No less than 0.5 mg of Meloxicam should be used to prevent the formation of colloids in the reaction medium. 75 μg of stannous chloride dihydrate was found to be sufficient to reduce all pertechnetate without the detection of free pertechnetate or colloids in the reaction mixture. The labeling should be done in alkaline solutions (pH 9–11). The labeled compound was separated and purified by HPLC. The biological distribution in infected mice demonstrates the suitability of 99mTc-labeled Meloxicam for inflammation and tumor imaging.