Interlaboratory comparability of serum cotinine measurements at smoker and nonsmoker concentration levels: A round-robin study
Interlaboratory comparability of serum cotinine measurements at smoker and nonsmoker concentration levels: A round-robin study
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DOI：
10.1093/ntr/ntp161
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发表时间：
2009-12-01
影响因子：
4.7
通讯作者：
Langman, Loralie J.
中科院分区：
文献类型：
--
作者：
Bernert, John T.;Jacob, Peyton, III;Langman, Loralie J.
可替宁是尼古丁的主要近代谢产物，通常作为烟草暴露指数来衡量，无论是活跃的烟草使用者还是可能接触二手烟 (SHS) 的非吸烟者。近年来，许多实验室已经对血清可替宁进行了测量分析，但实验室间对结果的比较很少。在接触二手烟的非吸烟者中，血液中可替宁的浓度可能相当低，并且过去曾报道过这些测量值存在很大的变异性。 在这项研究中，由七个实验室组成的小组（均具有血清可替宁分析经验）测量了八个编码血清库，其浓度范围从约 0.05 ng/ml 的背景水平到活跃吸烟者范围内相对较高的浓度。所有实验室都使用带有氮磷检测的气液色谱法或带有质谱检测的液相色谱法。所有七个实验室都可靠地测量了样品中可替宁的浓度，且均在其方法范围内。在每种情况下，池的结果均按顺序正确排序，并且任何池的结果在 5% 的显着性水平下均未观察到显着的实验室间偏差。我们的结论是，这些经验丰富的实验室所使用的血清可替宁色谱分析的现有方法能够在吸烟者和非吸烟者浓度范围内提供准确且精确的结果。
Cotinine, the primary proximate metabolite of nicotine, is commonly measured as an index of exposure to tobacco in both active users of tobacco and nonsmokers with possible exposure to secondhand smoke (SHS). A number of laboratories have implemented analyses for measuring serum cotinine in recent years, but there have been few interlaboratory comparisons of the results. Among nonsmokers exposed to SHS, the concentration of cotinine in blood can be quite low, and extensive variability in these measurements has been reported in the past.In this study, a group of seven laboratories, all experienced in serum cotinine analysis, measured eight coded serum pools with concentrations ranging from background levels of about 0.05 ng/ml to relatively high concentrations in the active smokers range. All laboratories used either gas-liquid chromatography with nitrogen-phosphorus detection or liquid chromatography with mass spectrometric detection.All seven laboratories reliably measured the cotinine concentrations in samples that were within the range of their methods. In each case, the results for the pools were correctly ranked in order, and no significant interlaboratory bias was observed at the 5% level of significance for results from any of the pools.We conclude that present methods of chromatographic analysis of serum cotinine, as used by these experienced laboratories, are capable of providing accurate and precise results in both the smoker and the nonsmoker concentration range.