Glossary · 2026-09-24
Scientific lead: Alice Kay, Ph.D.
Molecular weight of a research peptide
Molecular weight, on a peptide paperwork line, is the mass calculated for one named species. Free peptide, an acetate salt, and a trifluoroacetate salt do not share that number. Average mass and monoisotopic mass are also different calculations. The report should say which one it compared with the observed ion.
A catalog page may cite an approximate free-peptide mass for a defined sequence, as the pentadecapeptide note does for BPC-157. That sentence is not the mass on a later lot. Confirm the figure on the PDF. See the reading guide and pentadecapeptide. Research-use only.
Frequently asked questions
- Is the milligram size on the shop URL a molecular weight?
- No. A 10 mg catalog size is a labeled fill. Molecular weight is a mass per molecule for a stated species, usually in daltons.
- What if the PDF does not say average or monoisotopic?
- Do not guess. Quote the number that is printed and note that the calculation basis was not stated.
Research-use only. BlueNex Labs does not provide medical or veterinary advice. Confirm your institution’s policies before purchase.