Schulten H R, Palavinskas R, Kriesten K
Biomed Mass Spectrom. 1983 Mar;10(3):192-6. doi: 10.1002/bms.1200100315.
Field desorption mass spectrometry and stable isotope dilution have been used for direct trace analysis of metals in urine. Samples were collected over 24 h at 2 h intervals from a hospitalized multiple sclerosis patient. Quantitative determinations of Li+, Rb+, Mg2+ and Sr2+ from individual samples have been made and correlated with the amounts of urine excreted as well as with the time of day. The concentrations of Na+ and K+ were determined by flame photometry. The quantities of metals excreted in urine during the course of 24 h were 0.0129 mg for lithium, 4700 mg for sodium, 2100 mg for potassium, 1.4 mg for rubidium, 78.8 mg for magnesium and 0.2356 mg for strontium. The maximal absolute quantities excreted of all metals determined correspond with the largest volume of urine. The highest amounts of potassium, rubidium and strontium were found in urine during the daytime (8.00-20.00), whilst magnesium was excreted increasingly during the night hours (20.00-8.00). The excretion of lithium and sodium is fairly even over the entire 24 h period. It is noteworthy that similarities in the excretion profile and the concentration course are observed between Li+ and Na+ on one hand and between K+ and Rb+ on the other. Moreover, the lower concentration of Rb+ ions in urine of multiple sclerosis patients, in comparison to healthy individuals and clinical controls as reported previously, was confirmed.
场解吸质谱法和稳定同位素稀释法已用于尿液中金属的直接痕量分析。从一名住院的多发性硬化症患者身上，每隔2小时收集一次样本，共收集24小时。已对各个样本中的Li+、Rb+、Mg2+和Sr2+进行了定量测定，并将其与尿量以及一天中的时间进行了关联。通过火焰光度法测定Na+和K+的浓度。24小时内尿液中排出的金属量分别为：锂0.0129毫克、钠4700毫克、钾2100毫克、铷1.4毫克、镁78.8毫克和锶0.2356毫克。所有测定金属的最大绝对排出量与最大尿量相对应。白天（8:00 - 20:00）尿液中钾、铷和锶的含量最高，而镁在夜间（20:00 - 8:00）排出量逐渐增加。锂和钠在整个24小时内的排泄较为均匀。值得注意的是，一方面Li+和Na+之间，另一方面K+和Rb+之间，在排泄曲线和浓度变化过程中存在相似性。此外，与之前报道的健康个体和临床对照相比，多发性硬化症患者尿液中Rb+离子浓度较低这一情况得到了证实。
