Mass spectral libraries containing relevant endogenous and exogenous metabolites enable you to match to experimental MS/MS spectra for automatic dereplication. The number of compounds contained in these spectral libraries is an important factor and has continuously grown over recent years, enabling the identification of an increasing number of known metabolites.
This is reflected for example by the new version of the Bruker MetaboBASE Personal Library 2.0:
It contains MS/MS spectra of over 14,000 synthetic or isolated standards derived from the well known METLIN™(*) compound library, including di- and tri-peptides, in addition to endogenous and exogenous metabolites to study changes that occur in biological systems.
Well known metabolomic researchers, Prof. Gary Siuzdak and Dr. Paul Benton were instrumental in assembling the MS/MS spectra which have been acquired from Bruker QTOF instruments. All spectra were measured in positive and negative mode at different collision energies, and poor-quality spectra were discarded.
In-silico generated MS/MS spectra at collision energies of 10, 20 und 40 eV for more than 233,000 compounds in this library, paving the way for a faster tentative identification of relevant targets which are not yet available as pure reference standards.
Supplemental spectral data includes InCHi, SMILES, and CAS identifiers and synonyms for most substances. Database IDs and hyperlinks to external databases, including HMDB, METLIN, and PubChem, let you quickly bring identified metabolites into a biological context.
*METLIN™ is a trademark of THE Scripps Research Institute.
It is not only the number of spectra that matters, though also the quality of the data contained in the libraries, which is highly important for confident identification.
All spectra contained in the Bruker HMDB Metabolite Library 2.0 were manually inspected to remove noisy spectra and contaminant peaks. The masses of precursor and fragment ions were corrected to match the theoretical mass values and isotopic pattern distributions. Data for the Bruker HMDB Metabolite Library 2.0 was acquired using pure reference standards. All compounds were measured on an impact series QTOF high-resolution mass spectrometer using 5 different collision energy levels.
The second version of this spectral library provides more than 6000 MS/MS spectra for more than 800 compounds selected from the Human Metabolome Data Base (HMDB). Retention time information for reversed phase LC for approximately 600 metabolites adds further orthogonal information for increasing confidence in identification of metabolites found in, for example, urine, blood and other biofluids.
The T-Rex Elute Metabolomics-kit: RP is a dedicated Reversed-Phase LC column kit for enabling matching retention times to corresponding values in Bruker HMDB Metabolite Library 2.0. It also contains methods and Standard Operation Procedures (SOPs) for LC-MS/MS data acquisition and is part of the complete T-ReX LC-QTOF solution for simplified non-targeted metabolomics.
The Bruker HMDB Metabolite Library is exclusively provided by Bruker and was generated in collaboration with Prof. Liang Li and Prof. David Wishart and their teams at the University of Alberta, Canada.