NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Mass Spectrometry Fingerprints of Small-Molecule Metabolites in Biofluids. Building a Spectral Library of Recurrent Spectra for Urine Analysis.
Published
Author(s)
Yamil Simon, Ramesh Marupaka, Xinjian Yan, Yuxue Liang, Kelly H. Telu, Yuri A. Mirokhin, Stephen E. Stein
Abstract
A large fraction of ions observed in electrospray liquid chromatography-mass spectrometry (LC-MS) experiments of biological samples remain unidentified. One the main reasons for this is that spectral libraries of pure compounds fail to account for the complexity of the metabolite profiling of complex materials. Recently, the NIST Mass Spectrometry Data Center has been developing a novel type of searchable mass spectral library that include all recurrent unidentified spectra found in the sample profile. These libraries, in conjunction with the NIST tandem mass spectral library, allow analysts to explore most of the chemical space accessible to LC-MS analysis. In this work, we demonstrate how these libraries can provide a reliable fingerprint of the material by applying them to a variety of urine samples, including an extremely altered urine from cancer patients undergoing total body irradiation. The same workflow is applicable to any other biological fluid. The selected class of acylcarnitines is examined in detail and derived libraries and related software are freely available. They are intended to serve as online resources for continuing community review and improvement.
Simon, Y.
, Marupaka, R.
, Yan, X.
, Liang, Y.
, Telu, K.
, Mirokhin, Y.
and Stein, S.
(2019),
Mass Spectrometry Fingerprints of Small-Molecule Metabolites in Biofluids. Building a Spectral Library of Recurrent Spectra for Urine Analysis., Analytical Chemistry, [online], https://doi.org/10.1021/acs.analchem.9b02977
(Accessed October 10, 2025)