BPC-157 Molecular Weight, Sequence & Research Identity

BPC-157 is a research peptide consisting of 15 amino-acid residues, making it a pentadecapeptide. Its commonly cited reference sequence is GEPPPGKPADDAGLV, and PubChem identifies the neutral reference structure with molecular formula C62H98N16O22 and a computed average molecular weight of approximately 1,419.5 g/mol. These identifiers help laboratories compare a declared peptide with chemical reference records. They do not, by themselves, confirm the composition, amount or purity of material in a supplier's vial.

This guide explains BPC-157's reference sequence and mass, how research laboratories interpret peptide identity, and why a correct molecular formula is only one part of material verification.

What is BPC-157?

The name BPC-157 is used for a peptide containing 15 amino-acid residues. The alternate name bepecin appears in some chemical databases. In a laboratory setting, the most useful starting points are the complete amino-acid sequence, the exact chemical form being claimed and an authoritative reference identifier such as PubChem CID 9941957.

A peptide's identity is tied to more than a trade name. The order of residues matters, as do terminal modifications, stereochemistry and any salt or counterion relevant to the supplied material. Names on product listings should therefore be checked against explicit specifications rather than assumed to describe identical materials.

What is the BPC-157 amino-acid sequence?

The commonly recorded one-letter sequence is:

GEPPPGKPADDAGLV

In three-letter notation, the sequence is:

Gly–Glu–Pro–Pro–Pro–Gly–Lys–Pro–Ala–Asp–Asp–Ala–Gly–Leu–Val

It contains 15 residues. PubChem's reference entry represents the peptide with unmodified amino and carboxyl termini. A different claimed terminal form or modification would need its own corresponding chemical characterization; the reference entry must not be treated as a universal specification for every commercial preparation.

Why does sequence matter?

Two peptides can have similar masses yet differ in amino-acid order. A sequence provides a defined identity target against which suitable analytical evidence can be assessed. In addition to sequence information, laboratories may need to examine structural variants, impurities and whether the actual preparation matches the declared form.

What is the molecular formula and weight of BPC-157?

For the PubChem reference structure (CID 9941957):

• Peptide length: 15 amino acids
• Sequence: GEPPPGKPADDAGLV
• Molecular formula: C62H98N16O22
• Computed average molecular weight: Approximately 1,419.5 g/mol
• PubChem CID: 9941957
• Listed CAS identifier: 137525-51-0

A separate FDA substance-identity record gives an average mass of approximately 1,419.54 for the same formula. The small displayed difference reflects precision and rounding conventions, not evidence of a different tested batch.

Average molecular weight versus monoisotopic mass

An average molecular weight uses average atomic masses accounting for natural isotope abundances. A monoisotopic mass is calculated using specific isotopes. PubChem also lists a monoisotopic mass of about 1,418.7042 Da for the reference structure.

Mass-spectrometry reports may describe ions with different charges or adducts. Therefore, a measured mass-to-charge (m/z) value should not automatically be compared directly with the average neutral molecular weight without checking the ion assignment and method.

Does the reference molecular weight verify a vial of BPC-157?

No. A reference mass is a benchmark, not a certificate of authenticity or an analytical result. The supplied material could differ through declared or undeclared chemical modifications, counterions, moisture, residual solvents or the presence of other components. The actual composition of a particular sample requires relevant evidence tied to that sample or its identified batch.

Before relying on a product specification, researchers should verify that its sequence, formula, reported chemical form and stated molecular weight are mutually consistent. Any discrepancy should be reconciled with the supplier or responsible laboratory rather than silently adjusted.

How do laboratories assess BPC-157 research identity?

LC-MS and mass-based identification

Liquid chromatography–mass spectrometry (LC-MS) can combine chemical separation with mass-related evidence. It may support identity assessment when the method, expected ion patterns, observed signals and interpretation criteria are appropriate. A mass match alone may not distinguish every sequence isomer or impurity.

HPLC and chromatographic profiling

High-performance liquid chromatography (HPLC) can separate components and provide a chromatographic profile. In suitable methods, relative peak areas may be used to describe chromatographic purity. Such percentages do not automatically equal the fraction of total sample mass made up by the target peptide.

Additional analytical evidence

Depending on the research question, characterization may also involve other suitable measurements of peptide composition, identity or content. No single analytical output should be assumed to prove all possible quality attributes.

Why are identity and purity different?

Identity asks whether the target chemical entity is present and properly characterized. Purity asks how the sample compares with specified impurities or other measured components under a defined method. Content asks how much target material is present, which may require a separate quantitative approach.

A report that supports identity may not establish purity or amount. Conversely, a chromatogram dominated by one peak does not, on its own, establish the chemical identity of that peak.

For a practical explanation of these distinctions, see the companion article BPC-157 COA & HPLC Testing: What Research Buyers Should Check once it is published.

What documentation should researchers check?

A useful material record should include a clearly declared substance and chemical form, batch identifier, relevant dates, method descriptions, interpreted results and limitations. Where a supplier offers laboratory reports, researchers should verify that the report actually covers the material and batch being evaluated.

Review the BPC-157 product information and available laboratory documentation. These links are navigation references, not a claim that any particular Redline Bio Labs batch has been independently authenticated.

Frequently asked questions

How many amino acids are in BPC-157?

BPC-157 has 15 amino-acid residues in the commonly cited reference sequence, which is why it is described as a pentadecapeptide.

What is the molecular weight of BPC-157?

PubChem lists a computed average molecular weight of approximately 1,419.5 g/mol for its specified reference structure. A commercial sample may require additional chemical-form and batch verification.

Is BPC-157 molecular weight the same as measured vial content?

No. Molecular weight describes the mass of a chemical entity per mole; vial content is an amount of material in a container. They answer different questions.

Can HPLC alone confirm BPC-157 identity?

A chromatographic trace can provide useful separation information, but identity conclusions generally depend on the analytical method and potentially complementary evidence such as mass spectrometry.

Can a published chemical formula confirm a supplier's batch?

No. Formula and sequence are reference identifiers. Batch-specific claims require traceable, relevant documentation and evidence.

Conclusion

BPC-157 is represented in authoritative chemical reference data as a 15-residue peptide with sequence GEPPPGKPADDAGLV, formula C62H98N16O22, and computed average molecular weight close to 1,419.5 g/mol. These values provide a basis for scientific discussion, but do not certify any supplier's product. Good laboratory evaluation separates reference identity, analytical purity, measured content and traceable batch records.

Research use only: This educational article addresses chemical identity and laboratory documentation. It is not guidance for human or veterinary administration, dosing, or treatment.