Scope
Vesta is a supplier of research materials, not a research laboratory or a journal. The 51 compound pages, 10 research-area pages, the glossary and the guides are reference summaries written to help a laboratory read a certificate of analysis and check a batch. They describe identity data and analytical points. They do not describe any use, dose or effect in people or animals, and they are not medical advice.
Where the data comes from
Molecular formulas, CAS numbers and compound identifiers come from PubChem, the public chemical database of the US National Library of Medicine, retrieved through its PUG REST interface. Literature records come from PubMed through the NCBI E-utilities. For a small number of compounds that PubChem does not hold, the formula comes from the US FDA Global Substance Registration System. Retrieval date for the current data set: 2026-10-30.
40 of the 51 compounds have a PubChem formula on their page. Where no public record exists, the page says so instead of giving a number.
How masses are calculated
The monoisotopic mass is calculated from the molecular formula using the exact mass of the lightest isotope of each element, and the average molecular weight is calculated from the same formula using standard atomic weights. PubChem's own exact-mass field is not used for large peptides, because for them it can report the most abundant isotope peak instead of the monoisotopic one.
Expected ions are calculated as m/z = (M + z × 1.007276) / z for the protonated charge states. Sodium and potassium adducts use the atomic masses 22.989218 and 38.963158.
| Element | Monoisotopic mass (Da) | Average atomic weight |
|---|---|---|
| Carbon | 12.000000 | 12.0107 |
| Hydrogen | 1.007825 | 1.00794 |
| Nitrogen | 14.003074 | 14.0067 |
| Oxygen | 15.994915 | 15.9994 |
| Sulfur | 31.972071 | 32.065 |
| Phosphorus | 30.973762 | 30.973762 |
| Chlorine | 34.968853 | 35.453 |
| Cobalt | 58.933194 | 58.933195 |
How sequences are cross-checked
For peptides, the sequence is written out from the literature and the registry, a formula is computed residue by residue (with the N- and C-terminal groups and any ring closure), and the result is compared with the PubChem formula for the same compound. A page is marked as checked only when the two formulas are identical. 26 compounds passed this test. Where the two did not agree, the entry was corrected or the difference was noted on the page.
How literature is chosen
The selected papers (98 in total) are listed for scientific reference. They were chosen by title for relevance to the structure, analysis or biochemistry of the compound and were read back from PubMed by their PMID, so the title, journal and year are those of the indexed record. The list is a selection, not a systematic review, and a listed paper does not imply that Vesta supports any claim in it.
Blends and mixtures
For blends and mixed formulations the composition on the page is the manufacturer's specification, and the amounts are declared amounts per vial, not measurements for a batch. Where a composition is not itemised, the page says so and explains what to request. Where a structure is only reported in a public source and not confirmed by a registry (for example Adamax), the page labels the values as reported and unconfirmed.
Limits
The pages are prepared by the Vesta team from the sources above and have not been through peer review. A batch certificate of analysis always takes precedence over a reference value on this site. Salt form, counter-ion, metal content and water change the mass printed on a certificate, so compare like with like.
Corrections
If you find an error, write to support@vestapeptides.com with the page address and the source that disagrees with it. Corrections are made in the source data and the pages are rebuilt, and each page shows the date it was last built.
Machine-readable data
The same identity data is available as JSON at /data/compounds.json, and a text version of the reference content is at /llms-full.txt. See the compound index and the glossary.