Biodistribution (as determined by the radiolabelled equivalent) of a gold(III) bis(pyrrolide‐imine) Schiff base complex: a potential chemotherapeutic†. (16th July 2013)

• Record Type: Journal Article
• Authors: Akerman, Matthew P.; Munro, Orde Q.; Mongane, Modisenyane; van, Johan A.; Rae, William I. D.; Bester, Cornelius J.; Marjanovic‐Painter, Biljana; Szucs, Zoltan; Zeevaart, Jan Rijn; Atzrodt, Jens; Derdau, Volker
• Is Part Of: Journal of labelled compounds & radiopharmaceuticals. Volume 56:Number 9/10(2013)
• Page Start: 530
• Page End: 535
• Publication Date: 2013-07-16
• Subjects: Tracers (Chemistry) -- Periodicals; Radiopharmaceuticals -- Periodicals; 615.8424
• DOI: 10.1002/jlcr.3068
• Languages: English
• ISSNs: 0362-4803

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The biodistribution of an <italic>N</italic><sub>2</sub><italic>N</italic><sub>2</sub>′ tetradentate gold(III) chelate, which is known to be cytotoxic towards a range of human cancer cell lines, was determined by a radiolabelled equivalent of the compound. The <sup>198</sup>Au‐labelled gold(III) chelate of a bis(pyrrolide‐imine) Schiff base ligand with a three‐carbon di(azomethine) linkage was successfully synthesised with a high radiochemical yield of 73% and radiochemical purity of >95%. The high energy γ‐ray emitted by the <sup>198</sup>Au nucleus was used to follow the biodistribution of the compound <italic>in vivo</italic> in six male Sprague Dawley rats on a gamma camera. The log <italic>P</italic><sub>o/w</sub> value of the <sup>nat</sup>Au analogue, −1.92(2), showed that the compound is hydrophilic and therefore likely to largely remain in the blood pool. This was confirmed by the biodistribution study, which showed 21% of the injected dose (ID) remained in the blood pool 4.5 h after injection. This decreased to 10.8% over a 24‐h period. The activity measured in the lungs, 1.48%ID/g, remained relatively constant over a 24‐h period suggesting that the complex had accumulated in the lungs in the form of particulates, and could not be cleared by the test subjects. The <italic>t</italic><sub>½</sub> for the heart and lungs was greater than 24 h. Excretion of the test compound is seemingly via the kidneys, but is slow with approximately 30% of the ID excreted within 24 h.</p> </abstract>