Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, India.
Talanta. 2011 Dec 15;87:80-4. doi: 10.1016/j.talanta.2011.09.044. Epub 2011 Oct 1.
A relatively less expensive and less time consuming radio analytical technique for quantitative determination of Th(nat) in urine at mBq level is developed and reported in this paper. Th in urine is co-precipitated with Ca(3)(PO(4))(2) from wet oxidized urine matrix and the precipitate is dissolved in HNO(3) and evaporated to dryness. The residue is dissolved in 3M HCl and 200mg of Na-EDTA is added to mask Ca(2+), Mg(2+) and Fe(3+) ions. Th(4+) is extracted into 0.01M PC-88A (2-ethyl hexyl phosphonic acid mono-2-ethylhexyl ester), dissolved in toluene from the experimentally optimized pH 2.5 ± 0.3 in aqueous phase. Th(4+) is stripped into 8.0M HCl and evaporated to dryness. The content of the beaker is dissolved in pH 1.8 HCl and complexed with 3-hydroxy flavone. The sample is excited at 397 nm and fluorescence intensity is measured at 462 nm. The detailed study of the method is presented in this paper. Interference study on elements that are normally present in urine and other actinides (if present) is also given.
本文介绍了一种相对廉价且耗时较短的放射性分析技术，可用于在毫贝克级水平定量测定尿液中的天然钍(nat)。尿液中的钍与湿氧化尿液基质中的 Ca(3)(PO(4))(2)共沉淀，沉淀物用 HNO(3)溶解并蒸发至干。残渣用 3M HCl 溶解，加入 200mg 的 Na-EDTA 以掩蔽 Ca(2+)、Mg(2+)和 Fe(3+)离子。Th(4+)用 0.01M PC-88A（2-乙基己基膦酸单-2-乙基己基酯）从实验优化的 pH 值 2.5±0.3 的水相中萃取，萃取到甲苯中。Th(4+)用 8.0M HCl 反萃取并蒸发至干。将烧杯中的内容物溶解在 pH 1.8 HCl 中，并与 3-羟基黄酮络合。样品在 397nm 处激发，在 462nm 处测量荧光强度。本文详细介绍了该方法。还对尿液中通常存在的元素和其他锕系元素（如果存在）进行了干扰研究。
