Did you know that a growing number of chemicals in PubChem contain spectral information?
There are now more than 300 thousand chemicals with spectral information available, including 13C NMR, 1H NMR, 2D NMR, ATR-IR, FT-IR, GC-MS, Raman, UV-Vis, vapor-phase IR, and more. This content comes primarily from four data sources: the NIST/EPA/NIH Mass Spectral Library, the Hazardous Substances Data Bank (HSDB), the Human Metabolome Database (HMDB), and a new addition, SpectraBase.
The NIST/EPA/NIH Mass Spectral Library includes images of the top-three peaks of GC-MS or MS-MS spectra along with related metadata and annotation for more than two hundred thousand chemicals. The Library’s annotation includes instrument, collision energy, spectrum type, and associated metadata information.
SpectraBase, provided by Bio-Rad, a commercial publisher of spectral databases and spectroscopy software, includes images of, annotation about, and links to a diverse set of spectral information for tens of thousands of compounds. SpectraBase content includes extensive annotation and a variety of metadata, such as the instrument, measurement technique, sample source, and spectrum source, in addition to the image of the spectra.
For all four sources, additional spectral information is often available directly from the source and easily accessed using the links on the PubChem page.
How to find and access spectral data for a compound?
PubChem records with spectral data have a Table of Content (TOC) section labelled “Chemical and Physical Properties” with a “Spectral Properties” subsection. One can use the TOC to jump to a given type of spectral data content. Clicking the SpectraBase image or the HMDB link directs the user to an external web page for that compound, where one can further interact with the spectral information.
The PubChem Classification Browser (https://pubchem.ncbi.nlm.nih.gov/classification/#hid=72) can help you locate all PubChem Compound records containing a particular type of spectral information. The “Spectral Properties” node can be found under the “Chemical and Physical Properties” section in the PubChem Compound Table of Contents (TOC) classification tree.