Document Type : Research Paper

Authors

• A Hakimi
• A.R. Jalilian
• A Bahrami Samani
• M Ghannadi Maragheh

Abstract

Development of oral therapeutic radiopharmaceuticals is a new concept in radiopharmacy. Due to the interesting therapeutic properties of ¹⁷⁷Lu and oral bioavailability of maltolate (MAL) metal complexes, ¹⁷⁷Lu-maltolate (¹⁷⁷Lu-MAL) was developed as a possible therapeutic compound for ultimate oral administration. The specific activity of 2.6-3 GBq/mg was obtained by irradiation of natural Lu₂O₃ sample with thermal neutron flux of 4×10¹³ n.cm^-2.s^-1 for Lu-177. The product was converted into chloride form which was further used for labeling maltol (MAL). At optimized conditions a radiochemical purity of about >99% was obtained for ¹⁷⁷Lu-MAL shown by ITLC (specific activity, 970-1000 Mbq/mmole). The stability of the labeled compound as well as the partition coefficient was determined in the final solution up to 24h. Biodistribution studies of Lu-177 chloride and ¹⁷⁷Lu-MAL were carried out in wild-type rats for post-oral distribution phase data. Lu-MAL is a possible therapeutic agent in human malignancies for the bone palliation therapy so the efficacy of the compound should be tested in various animal models.
 

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Keywords

• Maltolate
• Lu-177
• Biodistribution
• Radiolabeling