RESUMO
INTRODUCTION: In this study, 68Ga-PDTMP was introduced as a novel agent for PET bone scanning. METHODS: 68Ga-PDTMP was prepared with radiochemical purity of higher than 98% at the optimized conditions. RESULTS: Stability tests showed no decrease in radiochemical purity, even after 120 min. The capacity binding of 76.3% ± 0.7% after 10 min incubation for 68Ga-PDTMP was observed. CONCLUSION: Biological studies in normal mice demonstrated that most of the remained activity is transmitted from blood into bones. The results show that 68Ga-PDTMP can be considered as a potential radiolabelled complex for PET bone scanning.
Assuntos
Osso e Ossos/diagnóstico por imagem , Difosfonatos/administração & dosagem , Difosfonatos/química , Radioisótopos de Gálio/administração & dosagem , Radioisótopos de Gálio/química , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/síntese química , Animais , Osso e Ossos/metabolismo , Difosfonatos/farmacocinética , Radioisótopos de Gálio/farmacocinética , Masculino , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Ratos , Distribuição TecidualRESUMO
OBJECTIVE: In this study, the human absorbed dose of holmium-166 ((166)Ho)-pamidronate (PAM) as a potential agent for the management of multiple myeloma was estimated. METHODS: (166)Ho-PAM complex was prepared at optimized conditions and injected into the rats. The equivalent and effective absorbed doses to human organs after injection of the complex were estimated by radiation-absorbed dose assessment resource and methods proposed by Sparks et al based on rat data. The red marrow to other organ absorbed dose ratios were compared with these data for (166)Ho-DOTMP, as the only clinically used (166)Ho bone marrow ablative agent, and (166)Ho-TTHMP. RESULTS: The highest absorbed dose amounts are observed in the bone surface and bone marrow with 1.11 and 0.903 mGy MBq(-1), respectively. Most other organs would receive approximately insignificant absorbed dose. While (166)Ho-PAM demonstrated a higher red marrow to total body absorbed dose ratio than (166)Ho-1,4,7,10-tetraazacyclo dodecane-1,4,7,10 tetra ethylene phosphonic acid (DOTMP) and (166)Ho-triethylene tetramine hexa (methylene phosphonic acid) (TTHMP), the red marrow to most organ absorbed dose ratios for (166)Ho-TTHMP and (166)Ho-PAM are much higher than the ratios for (166)Ho-DOTMP. CONCLUSION: The result showed that (166)Ho-PAM has significant characteristics than (166)Ho-DOTMP and therefore, this complex can be considered as a good agent for bone marrow ablative therapy. ADVANCES IN KNOWLEDGE: In this work, two separate points have been investigated: (1) human absorbed dose of (166)Ho-PAM, as a potential bone marrow ablative agent, has been estimated; and (2) the complex has been compared with (166)Ho-DOTMP, as the only clinically used bone marrow ablative radiopharmaceutical, showing significant characteristics.
Assuntos
Medula Óssea/efeitos dos fármacos , Complexos de Coordenação/farmacocinética , Compostos Organometálicos/farmacocinética , Organofosfonatos/farmacocinética , Compostos Organofosforados/farmacocinética , Radioisótopos/farmacocinética , Absorção de Radiação , Animais , Complexos de Coordenação/síntese química , Hólmio , Humanos , Mieloma Múltiplo/tratamento farmacológico , Especificidade de Órgãos , Compostos Organometálicos/síntese química , Organofosfonatos/síntese química , Compostos Organofosforados/síntese química , Doses de Radiação , Ratos , Distribuição TecidualRESUMO
In this work, the absorbed dose to human organs for (175)Yb-BPAMD was evaluated based on the biodistribution studies in rats. The results showed that the bone surface would receive the highest absorbed dose after injection of (175)Yb-BPAMD with 13.32mGy/MBq, while the other organs receive insignificant absorbed dose. Also, the comparison of (175)Yb-BPAMD with other therapeutic phosphonate complexes demonstrated noticeable characteristics for this new agent. Generally, based on the obtained results, (175)Yb-BPAMD can be considered as a promising agent for bone pain palliative therapy in near future.
