Metabolite Profiling of a NIST Standard Reference Material for Human Plasma (SRM 1950): GC-MS, LC-MS, NMR, and Clinical Laboratory Analyses, Libraries, and Web-Based Resources

Recent progress in metabolomics and the development of increasingly sensitive analytical techniques have renewed interest in global profiling, i.e., semiquantitative monitoring of all chemical constituents of biological fluids. In this work, we have performed global profiling of NIST SRM 1950, “Metabolites in Human Plasma”, using GC-MS, LC-MS, and NMR. Metabolome coverage, difficulties, and reproducibility of the experiments on each platform are discussed. A total of 353 metabolites have been identified in this material. GC-MS provides 65 unique identifications, and most of the identifications from NMR overlap with the LC-MS identifications, except for some small sugars that are not directly found by LC-MS. Also, repeatability and intermediate precision analyses show that the SRM 1950 profiling is reproducible enough to consider this material as a good choice to distinguish between analytical and biological variability. Clinical laboratory data shows that most results are within the reference ranges for each assay. In-house computational tools have been developed or modified for MS data processing and interactive web display. All data and programs are freely available online at http://peptide.nist.gov/ and http://srmd.nist.gov/.

代谢组学（metabolomics）领域的最新进展，以及灵敏度不断提升的分析技术的发展，重新唤起了学界对全局代谢谱分析（global profiling）——即对生物体液中全部化学成分开展半定量检测——的研究兴趣。本研究采用气相色谱-质谱联用（Gas Chromatography-Mass Spectrometry, GC-MS）、液相色谱-质谱联用（Liquid Chromatography-Mass Spectrometry, LC-MS）与核磁共振波谱（Nuclear Magnetic Resonance, NMR）三种技术，对美国国家标准与技术研究院标准参考物质1950（National Institute of Standards and Technology Standard Reference Material 1950, NIST SRM 1950，"人血浆代谢物"）开展了全局代谢谱分析。本研究探讨了各实验平台下的代谢组覆盖范围、实验难点与可重复性。该标准物质中共鉴定出353种代谢物。气相色谱-质谱联用技术可实现65种独有代谢物的鉴定；除部分无法被液相色谱-质谱联用技术直接检测到的小分子糖类外，核磁共振波谱得到的大部分鉴定结果均与液相色谱-质谱联用的鉴定结果重合。此外，重复性与中间精密度分析结果表明，SRM 1950的谱分析具备足够良好的可重复性，可作为区分分析变异与生物学变异的理想参考材料。临床实验室数据显示，本研究的多数检测结果均处于各检测方法的参考范围内。本研究开发并优化了用于质谱数据处理与交互式网页展示的自研计算工具。所有实验数据与程序均可通过以下网址免费获取：http://peptide.nist.gov/ 与 http://srmd.nist.gov/.