Effect of reaction conditions on preparations of rhenium-188 hydroxyethylidene diphosphonate complexes

• Published in: Nuclear medicine and biology 1999-05, Vol.26 (4), p.455-459
• Main Authors: Lin, Wan-Yu, Hsieh, Jih-Fang, Lin, Chih-Phoon, Hsieh, Bor-Tsung, Ting, Gann, Wang, Shyh-Jen, Knapp, Furn F
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Carrier; Diseases of the osteoarticular system; Drug Stability; Etidronic Acid - chemical synthesis; Etidronic Acid - chemistry; Etidronic Acid - pharmacokinetics; Hydrogen-Ion Concentration; Isotope Labeling; Male; Medical sciences; Rats; Rats, Sprague-Dawley; Re-188 HEDP complexes; Rhenium; Rhenium-186; Tissue Distribution; Tumors of striated muscle and skeleton
• ISSN: 0969-8051; 1872-9614
• DOI: 10.1016/S0969-8051(99)00007-4

Rhenium-186 (Re-186) hydroxyethylidene diphosphonate (HEDP) has been shown to localize in metastatic foci within bone in a manner similar to Tc-99m bone-seeking agents. Usually, in the preparation of diagnostic Tc-99m radiopharmaceuticals, the concentration of Tc is at trace level (10 −8 M). However, large amounts of carrier are included in the preparation of Re-186 radiopharmaceuticals (10 −4 M), which may significantly affect the preparation of Re-HEDP. In this study, Re-188 was used as an Re tracer. The effects of pH and concentrations of Re carrier on the preparation of Re-HEDP were investigated. Re-188-Sn-HEDP was prepared by reconstitution of a kit of lyophilized HEDP mixture, and tin chloride with a radioactive solution of perrhenate in saline. The total concentration of Re present in this work ranged from 10 −8 to 10 −3 M. The results showed that high labeling efficiency was obtained for each preparation. Although the chemical behaviors of the Re-188 HEDP complexes, with and without carrier, were similar, the biodistribution patterns of carrier free Re-188 HEDP in rats were found to differ from the biodistribution patterns of carrier-added Re-188 HEDP.