Fuente Ana de la, Zanca Roberta, Boni Roberto, Cataldi Angela G, Sollini Martina, Lazzeri Elena, Mariani Giuliano, Erba Paola A
Regional Center of Nuclear Medicine, University of Pisa, Pisa, Italy; and.
Nuclear Medicine Unit, Department of Oncology and Advanced Technology, "Arcispedale Santa Maria Nuova"-IRCCS, Reggio Emilia, Italy.
J Nucl Med Technol. 2017 Sep;45(3):236-240. doi: 10.2967/jnmt.115.154484. Epub 2017 Jul 13.
Quick methods are functional in clinical practice to ensure the fastest availability of radiopharmaceuticals. For this purpose, we investigated the radiochemical purity of the widely used Tc-hydroxymethylene diphosphonate, Tc-hexamethylpropyleneamine oxime, and Tc-tetrofosmin by reducing time as compared with the manufacturer's method. We applied a miniaturized chromatographic method with a reduced strip development from 18 cm to 9 cm for all 3 radiopharmaceuticals. The specific support medium and solvent system of the manufacturer's methods was kept unchanged for Tc-hydroxymethylene diphosphonate and Tc-tetrofosmin, whereas for Tc-hexamethylpropyleneamine oxime the instant thin-layer chromatography (ITLC) polysilicic gel (silicic acid [SA]) was replaced with a monosilicic gel (silicic gel [SG]) in the chromatographic system that uses methyl ethyl ketone as solvent. The method was applied and compared with the routine ITLC insert method in a total of 30 batches for each radiopharmaceutical. The precision of repeated tests was determined by comparison with the results of 10 replications on the same batch. Small volumes of concentrated TcO, and Tc-albumin nanocolloid were used to produce potential radiochemical impurities. Correlation between the quick methods and the insert methods was analyzed using a nonparametric 2-tailed test and a 2 × 2 contingency table with the associated Fisher exact test to evaluate sensitivity and specificity. A receiver-operating-characteristic analysis was performed to evaluate the best cutoff. The percentage radiochemical purity of the quick methods agreed with the standard chromatography procedures. We found that TcO and colloidal impurities are not the only common radiochemical impurities with Tc-tetrofosmin, and shortening of the ITLC strip with respect to the manufacturer's method will worsen system resolution and may produce inaccuracy. The miniaturized methods we described represent a fast and reliable alternative for Tc-exametazime and Tc-oxidronate quality control, with the upper cutoff for acceptable radiochemical purity values being 84% and 95%, respectively. For Tc-tetrofosmin radiochemical purity testing, a longer strip as described in the standard method is warranted.
快速方法在临床实践中发挥着作用,以确保放射性药物能最快可用。为此,我们通过与制造商的方法相比减少时间,研究了广泛使用的锝 - 羟基亚甲基二膦酸盐、锝 - 六甲基丙烯胺肟和锝 - 替曲膦的放射化学纯度。对于所有3种放射性药物,我们采用了一种小型化色谱方法,将展开条带从18厘米缩短至9厘米。对于锝 - 羟基亚甲基二膦酸盐和锝 - 替曲膦,制造商方法的特定支持介质和溶剂系统保持不变,而对于锝 - 六甲基丙烯胺肟,在以甲基乙基酮为溶剂的色谱系统中,即时薄层色谱(ITLC)多硅胶(硅酸[SA])被单硅胶(硅胶[SG])取代。该方法应用于每种放射性药物的总共30批次,并与常规ITLC插入法进行比较。通过与同一批次10次重复的结果比较来确定重复测试的精密度。使用少量浓缩的高锝酸盐和锝 - 白蛋白纳米胶体来产生潜在的放射化学杂质。使用非参数双尾检验和带有相关Fisher精确检验的2×2列联表分析快速方法与插入法之间的相关性,以评估敏感性和特异性。进行了受试者工作特征分析以评估最佳临界值。快速方法的放射化学纯度百分比与标准色谱程序一致。我们发现高锝酸盐和胶体杂质不是锝 - 替曲膦唯一常见的放射化学杂质,并且相对于制造商的方法缩短ITLC条带会降低系统分辨率并可能产生不准确结果。我们描述的小型化方法是锝 - 依美他嗪和锝 - 奥昔膦质量控制的快速且可靠的替代方法,可接受的放射化学纯度值的上限分别为84%和95%。对于锝 - 替曲膦放射化学纯度测试,需要标准方法中所述的更长条带。