Data Source
- MS DIAL Lipidome Atlas
- GNPS
- MassBank
- MoNA
- PNNL-Lipids
- MassSpecGym
*Preprocessing for comprehensive MS2 databases (like MassSpecGym) involved retaining only lipids by filtering the InChI Key main block using references from the MS DIAL Lipidome Atlas, LIPID MAPS and Swiss Lipids.
Dataset Description
| Column | Column Name | Description |
|---|---|---|
| 1 | index | A unique index for each spectrum. |
| 2 | name | Full lipid name including class and detailed acyl-chain notation (e.g. “PC 18:1/16:0”). |
| 3 | simple_name | Simplified lipid name summarizing total carbons and double bonds (e.g. “PC 34:1”). |
| 4 | class | Lipid class abbreviation (e.g. PC, PE, TAG). |
| 5 | chain | Acyl-chain composition string (e.g. “18:1/16:0”). |
| 6 | num_chain | The total number of acyl chains attached to the lipid backbone. |
| 7 | num_c | The total number of carbon atoms in all acyl chains combined. |
| 8 | num_db | The total number of carbon-carbon double bonds (C=C) in all acyl chains combined. |
| 9 | num_c_1 | Number of carbons in chain 1. Note: num_c_1 can be 0, but the num_c values for all four chains cannot all be 0 simultaneously. |
| 10 | num_db_1 | Number of C=C double bonds in chain 1. |
| 11 | num_c_2 | Number of carbons in chain 2. |
| 12 | num_db_2 | Number of C=C double bonds in chain 2. |
| 13 | num_c_3 | Number of carbons in chain 3. |
| 14 | num_db_3 | Number of C=C double bonds in chain 3. |
| 15 | num_c_4 | Number of carbons in chain 4. |
| 16 | num_db_4 | Number of C=C double bonds in chain 4. |
| 17 | precursor_mz | Mass-to-charge ratio (m/z) of the precursor ion. |
| 18 | adduct | Adduct ion type detected (e.g. [M+H]+, [M+Na]+). |
| 19 | ion_mode | Ionization mode (Positive or Negative). |
| 20 | charge | Observed charge state of the ion. |
| 21 | smiles | SMILES string representation of the molecule. |
| 22 | inchi | Full IUPAC InChI identifier. |
| 23 | inchikey | InChIKey. |
| 24 | inchikey_main | Main layer (first 14 characters) of the InChIKey. |
| 25 | exact_mass | Theoretical monoisotopic neutral mass. |
| 26 | formula | Chemical formula (e.g. C₃₆H₇₀O₈P). |
| 27 | synonyms | Alternative names. |
| 28 | retention_time | Liquid chromatographic retention time. |
| 29 | lib_quality | Library match quality score or confidence (1 is best). |
| 30 | source | Origin of the entry (database name). |
| 31 | spectrum_id | Unique identifier for the MS/MS spectrum in the source database. |
| 32 | ms_level | MS level of the spectrum. |
| 33 | instrument | Mass spectrometer used. |
| 34 | energy | Collision/fragmentation energy applied (e.g. 40 eV). |
| 35 | num_peaks | Number of peaks recorded in the MS2 spectrum. |
| 36 | MS2 | Raw MS2 spectrum in the format: [[mz1, int1], [mz2, int2]...]. "Raw" refers to data from the source, which may have already been normalized. |
| 37 | MS2_norm | Normalized MS2 intensities, scaled from 0–100. If more than 100 peaks, only the 100 highest-intensity peaks are retained. |
| 38 | MS2_frag_formula | The chemical formula for each fragment in the MS2 spectrum, corresponding to the peaks in MS2_norm. |
| 39 | ref | Chain information ignoring Sn position. Format: [total_carbons, total_double_bonds, c_chain1, db_chain1, c_chain2, db_chain2, ...]. Example: [38, 1, 18, 1, 20, 0] |