A new technique of 99mTc-ciprofloxacin kit preparation

I. Kleisner; P. Komarek; I. Komarkova; M. Konopkova

doi:10.1055/s-0038-1625292

Nuklearmedizin - NuclearMedicine, Table of Contents

Nuklearmedizin 2002; 41(05): 224-229
DOI: 10.1055/s-0038-1625292

Editorial

Schattauer GmbH

A new technique of ^99mTc-ciprofloxacin kit preparation

Neue Methode der Zubereitung des ^99mTc-Ciprofloxacin-Kits

I. Kleisner

¹Department of Nuclear Medicine, Kralovske Vinohrady University Hospital

,

P. Komarek

²Pharmaceutical Technology and Drug Control, Postgraduate Medical School

,

I. Komarkova

³Radiopharmacy, State Institute for Drug Control

,

M. Konopkova

⁴Nuclear Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic

› Author Affiliations

Abstract

Summary

Aim: Development of a simple and reproducible method for preparing a ciprofloxacin kit using a redox polymer, which would meet the requirements for an easy and reliable technique of labelling with ^99mTc and diagnostic efficiency in scintigraphic imaging of infections. Material and methods: To prepare the kit, an insoluble redox polymer containing an end α(β)-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 ^99mTc for 10 min at room temperature. The radiochemical purity of the ciprofloxacin-^99mTc complex was determined by ITLC and paper chromatography in relation to the following factors: pH, total content of ciprofloxacin, volume of sodium ^99mTc-pertechnetate. Ciprofloxacin biodistribution was evaluated in Wistar rats with Staphylococcus aureus infection in the left inguinal region 24 h after abscess induction. Accumulation of ^99mTc 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 3.3-3.7). With pH 3.45, labelled ciprofloxacin shows the highest stability and radiochemical purity. The ^99mTc-ciprofloxacin complex is stable for at least 8 h. In experimentally induced inflammation, the amount of accumulated ^99mTc-ciprofloxacin activity is five times higher than in controls. Conclusion: The developed method of ^99mTc-ciprofloxacin kit preparation employs a redox polymer in a new procedure, which enables the preparation of a stable kit with a high ^99mTc-labelling efficiency. The labelled kit is suitable for scintigraphic imaging of infection.

Zusammenfassung

Ziel: Entwicklung einer einfachen und reproduzierbaren Methode basierend auf einem Redoxpolymer zur verlässlichen Markierung und präzisen Szintigraphie von Infektionsherden. Methoden: Zur Herstellung des Kits wurde ein unlösliches Redoxpolymer mit endständiger α(β)-Alanin-N, N’-diazetatgruppe, gebunden an eine Dextranmatrix, benutzt. Das von den Autoren synthetisierte Redoxpolymer wurde in 5%iger Suspension 10 h bei Zimmertemperatur mit einer Ciprofloxacinlösung (1%) inkubiert. Danach wurde die filtrierte Mixtur in sterile Reagenzgläser gefüllt (je 0,2 ml). Die Markierung des Kits mit ^99mTc erfolgte bei Zimmertemperatur (Dauer: 10 min). Die radio-chemische Reinheit von ^99mTc-Ciprofloxacin wurde durch ITLC und Papierchromatographie getestet. Berücksichtigt wurden folgende Faktoren: pH, Ciprofloxacin-Gesamtgehalt, Natrium-^99mTc-pertechnetat-Volumen. Die Ciprofloxacin-Biodistribution wurde bei Wistar-Ratten mit abszessförmiger Staphylococcus-aureus-Infektion der linken Inguinalregion nach 24 h untersucht. Die Anreicherung der ^99mTc-Aktivität wurde mittels Gamma-kameraszintigraphie beurteilt. Ergebnisse: Radio-chemische Reinheit der Kit-Markierung >95% (pH 3,3-3,7). Bei pH 3,45 besitzt das markierte Ciprofloxacin die höchste Stabilität und radiochemische Reinheit. Der ^99mTc-Ciprofloxacin-Komplex bleibt mindestens 8 h stabil. Die Anreicherung von ^99mTcCiprofloxacin in Gewebe mit experimentell induzierter Entzündung ist fünfmal höher als im Kontrollgewebe. Schlussfolgerung: Die vorgestellte Methode der ^99mTcCiprofloxacin-Kit-Herstellung basierend auf einem neuartigen Redoxpolymer führt zu stabilen Kits mit hoher Markierung, die zur szintigraphischen Darstellung von Infektionen geeignet sind.

Keywords

Redox polymer - ^99mTc-ciprofloxacin kit - biodistribution - infection imaging

Schlüsselwörter

Redoxpolymer - ^99mTc-Ciprofloxacin-Kit - Biodistribution - Infektionsszintigraphie

Full Text

References

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