Rigorous, documented methodology you can trust. Three independent verification gates — mass, retention time, and spectral match — against a 40,000+ standard reference collection, delivering MSI Level 1a confidence.
The measured mass of the precursor ion is compared against the theoretical monoisotopic mass of every standard in the library, across both ESI+ and ESI− adduct series. Tolerance window ≤ 9 mDa; typical observed error ±0.6 mDa. Adducts screened include [M+H]+, [M+Na]+, [M+NH4]+, [M−H]−, [M+FA−H]− and [M+Cl]−.
Flavonols, flavones, flavanones, isoflavones, anthocyanins, biflavonoids — aglycones and O- and C-glycosides across all substitution patterns.
Caffeic, ferulic, sinapic, coumaric acids and their quinate, shikimate, and sugar esters, including chlorogenic acid isomers.
Tropane, isoquinoline, indole, and pyrrolizidine alkaloids, each with characterised fragment pathways.
Mono-, sesqui-, di-, and triterpenoids, including saponins with complex sugar chains.
Oxylipins, free fatty acids, glycerolipids, and phospholipids relevant to plant membrane biology.
Proteinogenic and modified amino acids, betaines, and small-molecule nitrogen metabolites.
Three orthogonal gates (mass, RT, MS²) agree against an authentic standard. Verified in both ESI+ and ESI−. This is what VeroMass delivers.
Matched to a library spectrum or diagnostic evidence, but no authentic standard is available for co-elution verification.
Assigned to a compound class based on spectral similarity or predicted properties. A hypothesis, not an identification.
In-silico tools that return ranked candidates based on predicted fragmentation do not reach Level 1a. However sophisticated the scoring, without a measured standard for RT and MS² validation, the answer is a probability, not an identity. VeroMass offers measured evidence, not ranked guesses.
≥ 0.85 minimum cosine score between submitted and library MS² spectrum. The library-wide median cosine for true matches is 0.965, well above the threshold.
Precursor mass tolerance of ≤ 9 mDa. The median observed error across all standards in both polarities is ±0.6 mDa, corresponding to sub-ppm accuracy on most small molecules.
RT gate set at ≤ 0.3 min vs. the authentic standard. Co-elution is verified by the RT predictor (R² = 0.986) and cross-checked against the measured library RT.
Every standard measured in both ESI+ and ESI−. Many metabolites ionise preferentially in one polarity; dual coverage ensures no compound is missed due to ionisation bias.
Each standard is fragmented at multiple collision energies (20, 35, 50 eV) to capture energy-dependent spectral variation and ensure robust matching across instrument types.
QC standards are reinjected every 20 samples to monitor mass drift, RT shift, and signal intensity. Acceptance criteria: mass error ≤ 3 mDa, RT shift ≤ 0.1 min over the entire batch.
The full methodology is documented above. If you are evaluating VeroMass and need additional detail for internal or peer review, contact us and we will provide it directly.