Labeling and Biodistribution of 99mTc-7-Bromo-1,4-dihydro-4-oxo-quinolin-3-carboxylic acid Complex
Wafaa Abdou Zaghary
Pharmaceutical Chemistry Department, King Saud University, Saudi Arabia
Abstract:
7-Bromo-1,4-dihydro-4-oxo-quinolin-3-carboxylic acid (4), was synthesized with a yield of 93% and well characterized. The obtained compound was investigated to label with one of the most important radioactive isotopes (technetium-99m). Effect of compound (4) concentration, stannous chloride dihydrates (SnCl2.2H2O) concentration, pH and reaction time on the percent labeling yield of 99mTc-(4) complex was studied. The formed complex was stable for a time up to 8 h with a maximum yield of 97.3%. This complex was obtained at a maximum yield by mixing 2.5mg of compound (4) with 25mg SnCl2.2H2O at pH 6 and 30min reaction time. Biodistribution studies in mice were carried out using experimentally induced infection in the left thigh using E. coli. Both thighs of the mice were dissected and counted to evaluate the ratio of bacterial infected thigh /contralateral thigh. Higher uptake in the infected thigh was observed after 2h of IV administration of 99mTc-(4) complex (T/NT =7.6 ± 1.6%) than that of the commercially available 99mTc-ciprofloxacin complex (T/NT =3.8 ±1%). The in vitro binding and biodistribution of 99mTc-(4) complex in the septic and aseptic inflammation bearing mice showed that, 99mTc-(4) complex is a promising agent for infection imaging and can differentiate between infected and inflamed muscle.
