Preparation and Biodistribution of Re-188 Sulfru Colloid

Kim, Young Ju; Jeong, Jae Min; Chang, Young Soo; Lee, Yong Jin; Lee, Dong Soo; Chung, June Key; Lee, Myung Chul; Song, Yeong Wook

Abstract

PURPOSE: We evaluated the usefulness of Re-188 sulfur colloid for radiation synovectomy and therapy of intraperitoneal metastasis.
MATERIALS AND METHODS
We investigated the labeling efficiency of Re-188 sulfur colloid on various conditions. The stability of Re-188 sulfur colloid was observed at room temperature for 24 h and in human serum and synovial fluid for 72 h. The particle size distribution of Re-188 sulfur colloid was rneasured by filtering with various pore size filters. Animal experiment was performed in mice and rabbits.
RESULTS
The labeling efficiency of Re-188 sulfur colloid was 64,5+/-5.8% (n=5) at the conditions of sodium thiosulfate 40 mg, EDTA Na2.2H2O 0,8 mg, KReO4 0.8 mg at pH l. After purification, the radiochemical purity was higher than 99%. The stability of Re-188 sulfur colloid was high (>99%) at room temperature for 24 h and in human serum and synovial fluid for 72 h. The particle size distribution of Re-188 sulfur colloid was 0.3% (<1 micrometer), 11.2% (1~5 micrometer), 35.8% (5~10 micrometer) and 52.8% (>10 micrometer). In mice, 1 h postinjection of Re-188 sulfur colloid into tail vein, uptakes in lung, liver and muscle were 37.30+/-5.36, 32.33+/-5.79, 6.60+/-0.02% 1D/organ respectively. After I.p. injection in rnice, the uptakes of extraperitonial organs of Re-188 sulfur colloid at 1 and 24 h were 0.1+/-0.1, 0.4+/-0.1% ID/organ, and the excretions through urine and feces (~70 h) were low (2.68+/-0.80, 0.95+/-0.17%). When Re-188 sulfur colloid was injected to synovial space of rabbit, the uptake in other organs except knee was very low.
CONCLUSION
Re-188 sulfur colloid showed high labeling efficiency, stability and potency for clinical use.