BACKGROUND Liver cancer is the 6 th most common cancer in the world and the 4 th most common death from cancer worldwide.Hepatic radioembolization is a minimally invasive treatment involving intraarterial administrati...BACKGROUND Liver cancer is the 6 th most common cancer in the world and the 4 th most common death from cancer worldwide.Hepatic radioembolization is a minimally invasive treatment involving intraarterial administration of radioembolic microspheres.AIM To develop a neutron-activated,biodegradable and theranostics samarium-153 acetylacetonate(153SmAcAc)-poly-L-lactic acid(PLLA)microsphere for intraarterial radioembolization of hepatic tumors.METHODS Microspheres with different concentrations of 152SmAcAc(i.e.,100%,150%,175%and 200%w/w)were prepared by solvent evaporation method.The microspheres were then activated using a nuclear reactor in a neutron flux of 2×10^12n/cm^2/s^1,converting 152Sm to Samarium-153(153)Sm)via 152Sm(n,γ) 153Sm reaction.The SmAcAc-PLLA microspheres before and after neutron activation were characterized using scanning electron microscope,energy dispersive X-ray spectroscopy,particle size analysis,Fourier transform infrared spectroscopy,thermo-gravimetric analysis and gamma spectroscopy.The in-vitro radiolabeling efficiency was also tested in both 0.9% sodium chloride solution and human blood plasma over a duration of 550 h.RESULTS The SmAcAc-PLLA microspheres with different SmAcAc contents remained spherical before and after neutron activation.The mean diameter of the microspheres was about 35μm.Specific activity achieved for 153SmAcAc-PLLA microspheres with 100%,150%,175%and 200%(w/w)SmAcAc after 3 h neutron activation were 1.7±0.05,2.5±0.05,2.7±0.07,and 2.8±0.09 GBq/g,respectively.The activity of per microspheres were determined as 48.36±1.33,74.10±1.65,97.87±2.48,and 109.83±3.71 Bq for 153SmAcAc-PLLA microspheres with 100%,150%,175%and 200%(w/w)SmAcAc.The energy dispersive X-ray and gamma spectrometry showed that no elemental and radioactive impurities present in the microspheres after neutron activation.Retention efficiency of 153Sm in the SmAcAc-PLLA microspheres was excellent(approximately 99%)in both 0.9%sodium chloride solution and human blood plasma over a duration of 550 h.CONCLUSION The 153SmAcAc-PLLA microsphere is potentially useful for hepatic radioembolization due to their biodegradability,favorable physicochemical characteristics and excellent radiolabeling efficiency.The synthesis of the formulation does not involve ionizing radiation and hence reducing the complication and cost of production.展开更多
To calculate a safe and effective 153Sm-EDTMP therapy dose, a whole-body scintigraphy technique for prospective individual dosimetry was developed and the results were compared with 5h urine collection method in 20 pa...To calculate a safe and effective 153Sm-EDTMP therapy dose, a whole-body scintigraphy technique for prospective individual dosimetry was developed and the results were compared with 5h urine collection method in 20 patients with bone metastases. Anterior and posterior whole-body images were obtained 10 min and 5 h after intravenous injection of 740 MBq 153Sm-EDTMP and the bone uptake value was determined. There is a close correlation between the bone uptake value obtained from the whole-body scintigraphy and 5 h urine collection method (r=0.93). The radiation absorption dose to red marrow was limited to 1.4 Gy and the administered activity calculated from bone uptake value by whole-body scintigraphy was 1.40-2.27GBq (mean 1.90 GBq). If the activity was calculated according to the standard body weight of 37 MBq.kg-1, the administered activity would be 1.75-2.41 GBq (mean 2.18), the radiation absorption dose to red marrow would be 1.37-2.27 Gy (mean 1.63 Gy), but at these doses significant myelotoxicity would be anticipated, thus emphasizing the need for individual prospective dosimetry.展开更多
基金Supported by Fundamental Research Grant Scheme sanctioned by the Ministry of Education,Malaysia,No.FRGS/1/2019/SKK06/TAYLOR/02/3。
文摘BACKGROUND Liver cancer is the 6 th most common cancer in the world and the 4 th most common death from cancer worldwide.Hepatic radioembolization is a minimally invasive treatment involving intraarterial administration of radioembolic microspheres.AIM To develop a neutron-activated,biodegradable and theranostics samarium-153 acetylacetonate(153SmAcAc)-poly-L-lactic acid(PLLA)microsphere for intraarterial radioembolization of hepatic tumors.METHODS Microspheres with different concentrations of 152SmAcAc(i.e.,100%,150%,175%and 200%w/w)were prepared by solvent evaporation method.The microspheres were then activated using a nuclear reactor in a neutron flux of 2×10^12n/cm^2/s^1,converting 152Sm to Samarium-153(153)Sm)via 152Sm(n,γ) 153Sm reaction.The SmAcAc-PLLA microspheres before and after neutron activation were characterized using scanning electron microscope,energy dispersive X-ray spectroscopy,particle size analysis,Fourier transform infrared spectroscopy,thermo-gravimetric analysis and gamma spectroscopy.The in-vitro radiolabeling efficiency was also tested in both 0.9% sodium chloride solution and human blood plasma over a duration of 550 h.RESULTS The SmAcAc-PLLA microspheres with different SmAcAc contents remained spherical before and after neutron activation.The mean diameter of the microspheres was about 35μm.Specific activity achieved for 153SmAcAc-PLLA microspheres with 100%,150%,175%and 200%(w/w)SmAcAc after 3 h neutron activation were 1.7±0.05,2.5±0.05,2.7±0.07,and 2.8±0.09 GBq/g,respectively.The activity of per microspheres were determined as 48.36±1.33,74.10±1.65,97.87±2.48,and 109.83±3.71 Bq for 153SmAcAc-PLLA microspheres with 100%,150%,175%and 200%(w/w)SmAcAc.The energy dispersive X-ray and gamma spectrometry showed that no elemental and radioactive impurities present in the microspheres after neutron activation.Retention efficiency of 153Sm in the SmAcAc-PLLA microspheres was excellent(approximately 99%)in both 0.9%sodium chloride solution and human blood plasma over a duration of 550 h.CONCLUSION The 153SmAcAc-PLLA microsphere is potentially useful for hepatic radioembolization due to their biodegradability,favorable physicochemical characteristics and excellent radiolabeling efficiency.The synthesis of the formulation does not involve ionizing radiation and hence reducing the complication and cost of production.
基金Supported by the National Natural Science Foundation of China (No.29971027)
文摘To calculate a safe and effective 153Sm-EDTMP therapy dose, a whole-body scintigraphy technique for prospective individual dosimetry was developed and the results were compared with 5h urine collection method in 20 patients with bone metastases. Anterior and posterior whole-body images were obtained 10 min and 5 h after intravenous injection of 740 MBq 153Sm-EDTMP and the bone uptake value was determined. There is a close correlation between the bone uptake value obtained from the whole-body scintigraphy and 5 h urine collection method (r=0.93). The radiation absorption dose to red marrow was limited to 1.4 Gy and the administered activity calculated from bone uptake value by whole-body scintigraphy was 1.40-2.27GBq (mean 1.90 GBq). If the activity was calculated according to the standard body weight of 37 MBq.kg-1, the administered activity would be 1.75-2.41 GBq (mean 2.18), the radiation absorption dose to red marrow would be 1.37-2.27 Gy (mean 1.63 Gy), but at these doses significant myelotoxicity would be anticipated, thus emphasizing the need for individual prospective dosimetry.
