Preparation and Biodistribution of 99mTc-Cloxacillin as a Novel Agent for Imaging Infection Caused by Staphylococcus aureus

Cloxacillin was labeled with Tc-99m using D-pencilamine as co-ligand and stannous chloride as reducing agent and its suitability for imaging S. aureus infections was assessed in vivo. Influence of various factors on labeling yield was studied, e.g. cloxacillin concentration, stannous chloride concentration, pH and reaction time. Biodistribution studies in rabbits were carried out in experimentally induced infection in left leg muscles using Staphylococcus aureus. Accumulation of Tc-99m-cloxacillin was high in infected leg muscles at 1 h post administration. Tc-99m-cloxacillin showed high stability, excellent pharmacokinetic behavior and high uptake of activity in infected leg muscles, which makes it a promising agent for imaging infection foci.