In-vitro binding assay study of 99mTc-flouroquinolones with E. coli, Salmonella and Ps. aeruginosa
A simple methodology was developed to evaluate binding efficiency of antibiotic members of fluoroquinolones, namely ciprofloxacin, ofloxacin and enorfloxacin, complexed with 99mTc, against Escherichia coli, Salmonella and Pseudomonas aeruginosa bacterial strains. Radioactivity in the pellet, tips supernatant and micro-centrifugation tubes was counted separately for 5 s in a sodium iodide well-counter with dedicated nuclear medicine software. The overall percentage activity of the live and killed bacteria was found in the range of 5–46% with different types of labelled quinolones and bacteria. Activity of the labelled enorfloxacin and ciprofloxacin indicated acceptable results for both live and killed E. coli and Ps. aeruginosa. However, ofloxacin was found to be moderate for all the live bacterial stains. This developed methodology has achieved more than 95% labelling efficiency of 99mTc with derivatized quinolones and also the observed results indicated that these complexes may be used as an infection specific imaging agents.