Peptide reference · Synthetic pentadecapeptide
BPC-157 COA check: molecular weight, formula and what to look for
Use these reference values to check the identity result on a BPC-157 Certificate of Analysis. The theoretical average molecular weight of BPC-157 is 1,419.54 Da and the monoisotopic mass is 1,418.704 Da.
Check a BPC-157 COA nowBPC-157 reference data
| Name | BPC-157 |
|---|---|
| Also known as | Body Protection Compound 157, PL 14736, Bepecin |
| Type | Synthetic pentadecapeptide |
| Molecular formula | C62H98N16O22 |
| Average molecular weight | 1,419.54 g/mol (Da) |
| Monoisotopic mass | 1,418.7042 Da |
| Residues | 15 |
| Sequence | Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val |
| Reference source | PubChem CID 9941957 (formula and mass cross-checked) |
Expected mass spectrometry ions
Electrospray (ESI) mass spectrometers measure mass-to-charge ratio (m/z), so a molecule can show up at several values depending on how many protons it picks up. If a BPC-157 COA lists one of these m/z values instead of the neutral mass, that is still consistent with BPC-157.
| Ion | m/z (monoisotopic) | m/z (average) |
|---|---|---|
| [M+H]+ | 1,419.71 | 1,420.55 |
| [M+2H]2+ | 710.36 | 710.78 |
| [M+3H]3+ | 473.91 | 474.19 |
Calculated from the molecular formula using a proton mass of 1.00728 Da. High-resolution instruments report monoisotopic values. Lower-resolution or deconvoluted results are often closer to the average mass.
What a good BPC-157 COA should show
- Identity by MS: a main mass within about ±1 Da of 1,419.54 (average) or 1,418.70 (monoisotopic), or one of the charge states above, with the spectrum image attached.
- Purity: ≥98% by HPLC (≥99% is excellent), with a chromatogram that shows retention time, peak area and a peak table.
- Traceability: the product name "BPC-157", a batch/lot number that matches your vial, a test date within the last 12 months, and the name of the testing lab.
- Independence: ideally a third-party lab with a report ID or QR code you can verify.
- Optional extras: net peptide content (actual mg per vial), endotoxin and heavy-metal results.
BPC-157-specific things to watch
BPC-157 is a 15-residue linear peptide with no unusual modifications, which makes it one of the easiest research peptides to verify by mass spectrometry. A single clean peak near 1419.5 Da (average) or 1418.7 Da (monoisotopic) is what you want to see.
Some vendors sell an arginate or acetate salt form. The salt counter-ion does not change the peptide's measured mass in ESI-MS, but it does lower the net peptide content per vial, so a COA that reports net peptide content is more informative than one that only reports gross weight.
Because BPC-157 is small and contains no cysteines, a common failure mode is not oxidation but truncation: look for side peaks in the HPLC trace that could correspond to deletion sequences from synthesis.
Compounds with similar mass
If a COA's mass is off, compare it with these neighbors. A match to one of them can point to a mislabeled product.
- Kisspeptin-10: 1,302.44 Da (-117.10 Da)
- PT-141: 1,025.16 Da (-394.38 Da)
- Melanotan II: 1,024.18 Da (-395.36 Da)
Sources
- PubChem CID 9941957: BPC-157 formula and reference mass.
- CIAAW: Standard atomic weights: Used to calculate average molecular weights.
- NIST CODATA: proton mass: Used to convert m/z charge states to neutral mass.
- PeptideCOACheck methodology: How the checker's thresholds work.
Last updated . Written and maintained under our editorial policy. Found an error? See corrections.
Frequently asked questions
What is the molecular weight of BPC-157?
The average molecular weight of BPC-157 (C62H98N16O22) is 1,419.54 Da and its monoisotopic mass is 1,418.7042 Da, calculated from the molecular formula and cross-checked against PubChem CID 9941957.
What mass should a BPC-157 COA show?
The mass spectrometry result should be within about ±1 Da of 1,419.54 Da (average) or 1,418.70 Da (monoisotopic), or show a matching charge-state ion such as 1,419.71 m/z.
What HPLC purity is good for BPC-157?
Most reputable suppliers target 98% or higher HPLC purity for BPC-157. 99% or higher is excellent. Below 95% is a warning sign.
How can I check a BPC-157 COA for free?
Enter the COA values into the free checker on PeptideCOACheck. It compares the reported mass with the theoretical value for BPC-157, checks purity, test date, batch number and lab name, and runs a red-flag checklist. Everything stays in your browser.
For laboratory research use only. This page describes analytical chemistry data. It is not medical advice and makes no claim about effects in humans or animals.