Abstract
Aim: Development of a simple and reproducible method for preparing a ciprofoxacin kit using a redox polymer, which would meet the requirements for an easy and reliable technique of labelling with Tc-99m and diagnostic efficiency in scintigraphic imaging of infections. Material and methods: To prepare the kit, an insoluble redox polymer containing an end alpha(beta)-alanine-N,N'-diacetate group anchored to the dextran matrix was used.
The redox polymer synthesised by the authors was incubated at room temperature (10 h) with a solution of ciprofloxacin (1%) in a suspension (5%). The mixture was then filtered and dispensed into sterile vials (0.2 ml each).
The kit was labelled with Tc-99m for 10 min at room temperature. The radiochemical purity of the ciprofloxacin-Tc-99m complex was determined by ITLC and paper chromatography in relation to the following factors: pH, total content of ciprofloxacin, volume of sodium Tc-99m-pertechnetate.
Ciprofloxacin biodistribution was evaluated in Wistar rats with Staphylococcus aureus infection in the left inguinal region 24 h after abscess induction. Accumulation of Tc-99m activity was determined both using external gamma camera imaging and counting dissected tissues 1 h after administration.
Results: Radiochemical purity is >95% for kit-labelling (pH 3.33.7). With pH 3.45, labelled ciprofloxacin shows the highest stability and radiochemical purity.
The Tc-99m-ciprofloxacin complex is stable for at least 8 h. In experimentally induced inflammation, the amount of accumulated Tc-99m-ciprofloxacin activity is five times higher than in controls.
Conclusion: The developed method of Tc-99m-ciprofloxacin kit preparation employs a redox polymer in a new procedure, which enables the preparation of a stable kit with a high Tc-99m-labelling efficiency. The labelled kit is suitable for scintigraphic imaging of infection.