Comparative biological evaluation between 99mTc(CO)3 and 99mTc-Sn (II) complexes of novel quinoline derivative: a promising infection radiotracer

A novel quinoline derivative, 2,2′-[(5-chloro-8-hydroxyquinoline-7-yl) methylazanediyl] diacetic acid (CHQMADA) was labeled with 99m Tc using SnCl 2 ·2H 2 O as a reducing agent to give a complex with a labeling yield 94 %. Also [ 99m Tc(H 2 O) 3 (CO) 3 ] + was prepared by heating at 100 °C for 30 min using 2 mg CHQMADA at pH 8 to give a labeling yield >99 %. 99m Tc-(CO) 3 CHQMADA and 99m Tc-Sn(II)-CHQMADA showed tissue uptake (target to non target T/NT = 6.80 ± 0.22) and (T/NT = 5.65 ± 0.34) respectively in Escherichia coli induced infection, which is higher than the commercially available 99m Tc-ciprofloxacin (T/NT = 3.80 ± 0.80). In conclusion, both complexes were able to differentiate between septic and aseptic inflammation with superiority of [ 99m Tc-(CO) 3 CHQMADA].