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Published on: November 28, 2017
Librarian: An Open-Access Web Application for High-Resolution Mass Spectral Library Assembly.
Jacob Ahlberg Weidenfors1, Bénilde Bonnefille2,3, Stefano Papazian2,3
1Unit of Integrative Metabolomics, Institute of Environmental Medicine, Karolinska Institutet, 17177 Stockholm, Sweden.
Metabolites
|June 25, 2026
Summary
Librarian is a new web application that simplifies the creation and sharing of mass spectral (MS2) libraries. This tool helps researchers build standardized, metadata-rich spectral records for improved chemical annotation in mass spectrometry.
Area of Science:
- Mass spectrometry
- Computational chemistry
- Data science
Background:
- High-quality tandem mass spectral (MS2) libraries are crucial for accurate chemical annotation in small-molecule mass spectrometry.
- Current challenges in standardizing and sharing MS2 data limit community participation and the growth of open-access repositories.
- Development of computational tools is needed to facilitate the creation and dissemination of MS2 reference libraries.
Purpose of the Study:
- To develop a user-friendly, scalable web application for assembling standardized, metadata-rich MS2 spectral records.
- To lower technical barriers for researchers contributing to open-access spectral databases.
- To promote broader community engagement in the development and sharing of high-resolution MS2 libraries.
Main Methods:
- Developed Librarian, a free, open-access web application for rapid MS2 library assembly.
- Integrated automated retrieval of chemical identifiers and metadata from PubChem.
- Facilitated compound mixture design for high-resolution mass spectrometry (HRMS) acquisition and curated MS2 spectra assembly.
- Ensured compatibility with public spectral databases and open-source pre-processing tools.
Main Results:
- Librarian provides an intuitive workflow for creating repository-ready MS2 records.
- Demonstrated Librarian's utility by generating and depositing over 1500 new MS2 records into MassBank.
- Successfully applied the generated library in retrospective analysis of environmental datasets.
Conclusions:
- Librarian effectively streamlines the generation of standardized, metadata-rich MS2 reference records.
- The application addresses a significant bottleneck in spectral library development and sharing for the scientific community.
- Librarian supports the expansion of open-access resources vital for metabolomics, exposomics, and environmental mass spectrometry research.
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