Burri Judith, Haldimann Max
Swiss Federal Office of Public Health, Division of Food Safety, Section Chemical Risks, Bern, Switzerland.
Clin Chem Lab Med. 2007;45(7):895-8. doi: 10.1515/CCLM.2007.153.
Selenium status in humans depends on nutritional intake. To facilitate a future monitoring study with a large number of samples, an inductively coupled plasma mass spectrometry (ICP-MS) analysis method including collision cell technology was developed for the direct determination of selenium in human serum.
Serum samples were diluted (1:15 v/v) with an aqueous solution containing 2-propanol, EDTA(NH(4))(2), ammonia and Triton X-100. Isotope dilution was used as the calibration method, evaluating the (78)Se/(82)Se ratio. Interference by (81)BrH(+) was corrected mathematically. Nebuliser blockage was prevented by sample centrifugation and filtration of the wash solution. Method validation was carried out using certified and spiked human sera.
All values obtained for the accuracy tests were either within the certified ranges or showed recovery between 100.9% and 104.7%. Further results were relative standard deviation of 2.0% for repeatability and 3.0% for between-run precision, a limit of detection of 0.5 mug/L and a limit of quantification of 1.1 microg/L.
The benefits of the new method are high accuracy combined with low sample consumption and fast sample throughput.
人体中的硒状态取决于营养摄入。为便于将来对大量样本进行监测研究，开发了一种包括碰撞池技术的电感耦合等离子体质谱（ICP-MS）分析方法，用于直接测定人血清中的硒。
血清样本用含有异丙醇、乙二胺四乙酸二铵、氨水和吐温X-100的水溶液稀释（1:15 v/v）。采用同位素稀释作为校准方法，评估（78）Se/（82）Se比值。通过数学方法校正（81）BrH(+)的干扰。通过样品离心和洗涤溶液过滤防止雾化器堵塞。使用经过认证和加标的人血清进行方法验证。
准确性测试获得的所有值均在认证范围内，或回收率在100.9%至104.7%之间。其他结果为重复性相对标准偏差为2.0%，批间精密度为3.0%，检测限为0.5μg/L，定量限为1.1μg/L。
新方法的优点是准确性高，同时样品消耗低且样品通量快。
