title: Automated module radiolabeling of peptides and antibodies with gallium-68, lutetium-177 and iodine-131.
abstract: Our objectives were to automate radiolabeling of therapeutic activities for safe, reliable, cost-effective, practical routine preparation of (177)Lu-radiopeptides, (131)I radioimmunotherapeutic agents, and (68)Ga-peptide PET diagnostics and, in particular, minimize radiation exposure to the radiopharmaceutical chemist. Reprogramming and adaptation of a commercially available synthetic module (IBA molecular; Synthera®) allowed high yield, fully automated, in-house radiolabeling of novel therapeutic and diagnostic radiopharmaceuticals under remote shielded sterile conditions. Radiochemical yield and purity was measured by instant thin-layer chromatography and high-performance liquid chromatography. (68)Ga-octreotate and (177)Lu-octreotate were synthesized, resulting in both radiochemical yield and radiochemical purity greater than 99%. Synthesis of (131)I-rituximab resulted in a yield of 60%, with a radiochemical purity greater than 99%. Using 400 MBq (68)GaCl(3) per synthesis, the estimated absorbed body and hand dose for a manual synthesis was 2 and 27 μ Sv, contrasting with automated synthesis exposure of 1.3 and 7.9 μ Sv. Using 8000 MBq (177)LuCl(3) per synthesis, the estimated absorbed body and hand dose for a manual synthesis was 44.7 and 75 μ Sv, contrasting with automated synthesis exposure of 2.5 and 20 μ Sv. Using 6000 MBq (131)I per synthesis, the estimated absorbed body and hand dose for a manual synthesis was 83.7 and 335 μ Sv, contrasting with automated synthesis exposure of 10.9 and 54.7 μ Sv. The reduction in radiation exposure by automated synthesis of radiopharmaceuticals in the Synthera® module was at least five fold. Automated synthesis of therapeutic (177)Lu and (131)I radiopharmaceuticals and (68)Ga PET agents in the shielded sterile Synthera® module is simple, practical, and efficient and virtually eliminates radiation exposure to the radiopharmaceutical chemist.
authors.affiliation: Department of Nuclear Medicine, The University of Western Australia, Fremantle Hospital, Fremantle, Australia.
authors.forename: Mario
authors.initials: M
authors.lastname: De Decker
authors.forename: J Harvey
authors.initials: JH
authors.lastname: Turner
mesh_terms: D000906:Antibodies / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D005710:Gallium Radioisotopes / Q000737:chemistry*; D006801:Humans; D007457:Iodine Radioisotopes / Q000737:chemistry*; D007553:Isotope Labeling / Q000379:methods*; D008187:Lutetium / Q000737:chemistry*; D010455:Peptides / Q000138:chemical synthesis*; D011868:Radioisotopes / Q000737:chemistry*; D019275:Radiopharmaceuticals / Q000138:chemical synthesis*
chemical_list: D000906:Antibodies; D005710:Gallium Radioisotopes; D007457:Iodine Radioisotopes; D010455:Peptides; D011868:Radioisotopes; D019275:Radiopharmaceuticals; D008187:Lutetium