State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Rapid Commun Mass Spectrom. 2020 Apr 15;34(7):e8658. doi: 10.1002/rcm.8658.
Molybdenum (Mo) is predominantly expelled from the human body in urine. Consequently, urinary variability in the concentration and isotopic composition of Mo may encode valuable clinical information. To access this information, however, it is first necessary to develop and demonstrate a rapid, accurate and precise methodology capable of concentrating Mo from urine for isotope analysis.
The utility of N-benzoyl-N-phenylhydroxylamine (BPHA) to effectively separate and purify Mo from urine samples without the need for acid digestion was tested. Following this approach, applying a double-spike mass bias correction, we determined the Mo isotopic compositions of a set of urine samples by multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS).
Based on replicate analyses of an in-house urine standard, this approach demonstrates an external precision on δ Mo values of better than 0.08‰ (2SD, n = 15). Application to a sample set collected from healthy individuals in Guangzhou, China, provides the first suite of δ Mo measurements from urine samples. Samples from the female participants show δ Mo (‰) values (1.31 ± 0.19‰, Ave ± 2SD, n = 14) that are consistently lower than those from the male participants (1.55 ± 0.16‰, Ave ± 2SD, n = 17).
The employed methodology is suitable for rapid, low-blank and high-throughput Mo isotope analysis of urine samples. Although resolvable δ Mo variability is seen in this preliminary dataset, the mechanism driving this variability is unknown. High-precision Mo isotopic analysis might be added to the urinalysis tool-kit, with the potential to provide valuable clinical information in the future.
钼（Mo）主要通过尿液从人体排出。因此，尿液中钼的浓度和同位素组成的变化可能会提供有价值的临床信息。然而，要获取这些信息，首先必须开发并验证一种快速、准确、精密的方法，能够从尿液中浓缩钼以进行同位素分析。
测试了 N-苯甲酰基-N-苯羟胺（BPHA）是否可以有效地将钼从尿液样品中分离和纯化，而无需进行酸消解。采用这种方法，应用双同位素质量偏差校正，我们通过多接收电感耦合等离子体质谱仪（MC-ICP-MS）测定了一组尿液样品的钼同位素组成。
基于内部尿液标准品的重复分析，该方法的外部分辨率δMo 值优于 0.08‰（2SD，n=15）。应用于在中国广州采集的健康个体样本集，提供了尿液样本中首个δMo 测量套件。女性参与者的样本显示 δMo（‰）值（1.31±0.19‰，Ave±2SD，n=14）持续低于男性参与者（1.55±0.16‰，Ave±2SD，n=17）。
所采用的方法适合于快速、低空白和高通量的尿液样品钼同位素分析。尽管在这个初步数据集上可以看到可分辨的δMo 变异性，但驱动这种变异性的机制尚不清楚。高精度钼同位素分析可能会被添加到尿液分析工具包中，未来有可能提供有价值的临床信息。
