Wong Yin How, Tan Hun Yee, Kasbollah Azahari, Abdullah Basri Johan Jeet, Yeong Chai Hong
School of Medicine, Faculty of Health and Medical Sciences, Taylor's University, Subang Jaya 47500, Selangor, Malaysia.
School of Biosciences, Faculty of Health and Medical Sciences, Taylor's University, Subang Jaya 47500, Selangor, Malaysia.
Pharmaceutics. 2019 Nov 12;11(11):596. doi: 10.3390/pharmaceutics11110596.
Transarterial radioembolization (TARE) has been proven as an effective treatment for unresectable liver tumor. In this study, neutron activated, Sm-labeled microspheres were developed as an alternative to Y-labeled microspheres for hepatic radioembolization. Sm has a theranostic advantage as it emits both therapeutic beta and diagnostic gamma radiations simultaneously, in comparison to the pure beta emitter, Y.
Negatively charged acrylic microspheres were labeled with Sm ions through electrostatic interactions. In another formulation, the Sm-labeled microsphere was treated with sodium carbonate solution to form the insoluble Sm carbonate (SmC) salt within the porous structures of the microspheres. Both formulations were neutron-activated in a research reactor. Physicochemical characterization, gamma spectrometry, and radiolabel stability tests were carried out to study the performance and stability of the microspheres.
The Sm- and SmC-labeled microspheres remained spherical and smooth, with a mean size of 35 µm before and after neutron activation. Fourier transform infrared (FTIR) spectroscopy indicated that the functional groups of the microspheres remained unaffected after neutron activation. The Sm- and SmC-labeled microspheres achieved activity of 2.53 ± 0.08 and 2.40 ± 0.13 GBq·g, respectively, immediate after 6 h neutron activation in the neutron flux of 2.0 × 10 n·cm·s. Energy-dispersive X-ray (EDX) and gamma spectrometry showed that no elemental and radioactive impurities were present in the microspheres after neutron activation. The retention efficiency of Sm in the SmC-labeled microspheres was excellent (99% in distilled water and saline; ~97% in human blood plasma), which was higher than the Sm-labeled microspheres (95% and ~85%, respectively).
SmC-labeled microspheres have demonstrated excellent properties for potential application as theranostic agents for hepatic radioembolization.
经动脉放射性栓塞术（TARE）已被证明是治疗不可切除肝肿瘤的有效方法。在本研究中，开发了经中子活化的钐标记微球，作为用于肝脏放射性栓塞的钇标记微球的替代物。与纯β发射体钇相比，钐具有治疗诊断优势，因为它同时发射治疗性β射线和诊断性γ射线。
通过静电相互作用用钐离子标记带负电荷的丙烯酸微球。在另一种配方中，用碳酸钠溶液处理钐标记的微球，以在微球的多孔结构内形成不溶性碳酸钐（SmC）盐。两种配方均在研究堆中进行中子活化。进行了物理化学表征、γ能谱分析和放射性标记稳定性测试，以研究微球的性能和稳定性。
钐和SmC标记的微球在中子活化前后均保持球形且表面光滑，平均尺寸为35 µm。傅里叶变换红外（FTIR）光谱表明，中子活化后微球的官能团未受影响。钐和SmC标记的微球在2.0×10 n·cm·s的中子通量中经6小时中子活化后，立即分别达到2.53±0.08和2.40±0.13 GBq·g的活度。能量色散X射线（EDX）和γ能谱分析表明，中子活化后微球中不存在元素杂质和放射性杂质。Sm在SmC标记微球中的保留效率极佳（在蒸馏水和盐水中约为99%；在人血浆中约为97%），高于钐标记微球（分别约为95%和85%）。
SmC标记的微球已显示出作为肝脏放射性栓塞治疗诊断剂潜在应用的优异性能。
