Determination of optimized conditions for 99mTc-labeled riphampicin Preparation for tuberculosis imaging applications

Developing of new infection imaging agents is a mandate in the detection of resistant species in the clinic due to the mortality of various new strains of bacteria including mycobacterium tuberculosis. In this study, various conditions were optimized for the rapid and efficient labeling of rifampicin antibiotic labeled with Tc-99m for ultimate use in infection imaging. Radiochemical purities were checked by RTLC using methyl ethyl ketone, and normal saline on Whatman No.1 paper. The time, temperature, ligand concentration, stannous ion amount, pH were optimized in the radiolabeling process and the best conditions were room temperature, pH 7, 20 micrograms of stannous chloride for 1 mg of rifampicin solid and 20 mCi of freshly milked technetium-99m pertechnetate. The complex demonstrated satisfactory stability in the presence of human serum and final formulations for 6 hours.