BPC-157: The Most-Researched Peptide in the Catalogue

Compound deep-dive

BPC-157 explained: the most-researched peptide in the catalogue.

A 15-amino-acid fragment derived from a Body Protection Compound first isolated from human gastric juice. Characterised at the University of Zagreb from 1991 onwards. Over 200 peer-reviewed papers. The unusual property that put it on the map: it survives gastric acid, which is something almost no peptide does.

By Marcus, founder· Published 6 May 2026· ~9 min read

TL;DR. BPC-157 is a synthetic 15-amino-acid peptide derived from a larger Body Protection Compound (BPC) first isolated from human gastric juice and characterised by Predrag Sikiric and the gastroenterology research group at the University of Zagreb beginning in 1991. The full sequence is GEPPPGKPADDAGLV with an average molecular weight of 1419.55 g/mol. The defining property in the published literature is its unusual stability in low-pH and protease-rich environments, which is what triggered the volume of follow-up preclinical research that has accumulated since. Verify a real batch the same way you verify any peptide: a clean single-peak HPLC chromatogram at 99%+ purity, mass-spectrometry confirmation of the 1419.55 g/mol average mass, and a uniform white lyophilised cake. Research use only.

What BPC-157 actually is

The full name is Body Protection Compound 157. The “157” refers to the position of the 15-residue active fragment within a larger ~40-kDa protective protein originally isolated from human gastric juice. The Zagreb group identified the active region, characterised it, and synthesised it as a defined peptide for use as a research tool. That synthesised fragment is what the research-peptide market sells as BPC-157.

The sequence is fifteen amino acids long, written in standard one-letter notation as GEPPPGKPADDAGLV. In full: glycyl-glutamyl-prolyl-prolyl-prolyl-glycyl-lysyl-prolyl-alanyl-aspartyl-aspartyl-alanyl-glycyl-leucyl-valine. The unusual feature of the sequence is the proline cluster at residues 3-4-5 and again at residue 8, which contributes meaningful conformational rigidity. That rigidity is the structural reason the molecule resists hydrolysis in environments that would tear most peptides apart.

Sequence	`Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val` (single-letter: `GEPPPGKPADDAGLV`)
Length	15 amino acids (pentadecapeptide)
Average MW	1419.55 g/mol
Monoisotopic MW	1418.69 Da
CAS number	137525-51-0
Source organism (parent BPC)	Human gastric juice (Sikiric et al., Zagreb)
Stability in solution	Reported as unusually stable across the gastric pH range and in human gastric juice for hours in published in-vitro work
Lyophilised stability	24+ months at 2–8 °C, sealed and protected from light
Light sensitivity	Lower than copper-bound peptides; standard practice is still amber glass

How BPC-157 was discovered

The story starts in the late 1980s and early 1990s in the gastroenterology department at the University of Zagreb, Croatia, with a research group led by Predrag Sikiric. The team’s working interest was in cytoprotection, the idea (originating with the Hungarian-Canadian endocrinologist Hans Selye and developed for the gut by Andre Robert) that gastric mucosa contains its own defence machinery against acid, alcohol, and stress.

Sikiric’s team isolated a body-protective compound (BPC) from human gastric juice that maintained its activity in cell-based assays through conditions that should have destroyed any normal peptide. They identified a defined 15-residue active fragment, characterised it by sequencing and mass spectrometry, and published the synthetic version under the laboratory designation BPC-157. From 1991 onwards the group, and a growing list of collaborators, accumulated a preclinical literature base in rodent injury models that now exceeds 200 peer-reviewed papers. PubMed indexes the bulk of them. Two useful entry points if you want to read the original work are Sikiric et al. (2016), “Brain-gut Axis and Pentadecapeptide BPC 157”, and Sikiric et al. (2018), “Stable Gastric Pentadecapeptide BPC 157, Robert’s Stomach Cytoprotection / Adaptive Cytoprotection, and Selye’s Stress Coping Response”. Both are open-access reviews that summarise large portions of the underlying body of work.

Why the stability matters

Most peptides die in stomach acid. This one doesn’t.

Standard peptide pharmacology assumes oral bioavailability of effectively zero, because the gut breaks the peptide bond with a battery of acid hydrolysis and protease enzymes that any normal short peptide cannot survive. That is why peptide drugs are typically delivered by injection or intranasal routes, not by mouth.

BPC-157 is reported in the published in-vitro literature to retain activity after exposure to human gastric juice over a multi-hour timescale. The proline-rich N-terminal region and the overall sequence rigidity are widely thought to be responsible. The relevance for the research-peptide market is that this property is the single feature that drove the original interest from Zagreb and sustains the volume of follow-up work that the compound has accumulated.

It also has consequences for analytical handling at the bench: BPC-157 is more forgiving than fragile peptides like Selank, but the standard cold-chain practice of refrigerated transport in amber glass is still the right default.

What the published literature actually covers

The core preclinical literature spans several research areas, all in cell-based or rodent models:

Gastrointestinal-tract research models. The original mucosal-cytoprotection context. Models of acid-induced ulcer, alcohol-induced ulcer, NSAID-induced gastropathy, and inflammatory-bowel-disease analogues form the foundation of the Zagreb work.
Tendon and ligament repair models. Rat Achilles transection, medial collateral ligament transection, and rotator-cuff tear models. Most of the visibility BPC-157 has in non-academic discussion of “research peptides for recovery” comes from this body of work.
Vascular endothelium and the nitric-oxide pathway. A subset of the published literature characterises BPC-157 in models that touch the eNOS / NO pathway, which the Zagreb group argues is part of its mechanism.
Central-nervous-system and brain-gut-axis work. Models of stroke, traumatic-brain-injury analogues, depression and anxiety analogues drawn from the Selye stress-coping framework.
Drug-induced toxicity models. Cardiac, hepatic, and renal toxicity analogues across a range of agents.

If you want the broadest single overview, the Sikiric 2018 review cited above pulls the gastric, tendon, vascular, and CNS strands together with the original mechanistic framing. The volume and breadth of the literature is the genuinely unusual feature of BPC-157 compared to most other research peptides on the market: it is the most-published peptide in this category by a clear margin.

None of the above is a therapeutic claim. The published preclinical context is rodent injury models and in-vitro cell systems. There are no peer-reviewed phase 3 randomised controlled trials in humans for BPC-157, and BPC-157 is not approved as a medicine by the MHRA in the UK or by the FDA in the US. We sell it strictly as a research-grade reference reagent for laboratory and in-vitro use only.

What to look for on the Certificate of Analysis

The standard COA for BPC-157 in our market is issued by Janoshik Analytical, an independent specialist peptide analysis lab in the Czech Republic. Our walk-through of how to read a Janoshik HPLC report covers the structure line by line. For BPC-157 specifically there are three things worth singling out:

1. A single dominant peak at the BPC-157 retention time

On a reversed-phase HPLC chromatogram BPC-157 elutes at a characteristic retention time for the column and gradient the lab is using. You should see one tall peak, a flat baseline elsewhere, and purity reported in the analytical summary at 99% or higher. Multiple peaks of comparable height in the chromatogram suggest a mixed synthesis product or partial degradation, neither of which is what you want for analytical reference work.

2. Mass-spectrometry confirmation of the 1419.55 g/mol average mass

Where the lab includes MS data, the singly protonated molecular ion in positive ion mode lands at m/z 1420.55. A doubly protonated species at m/z 710.78 is also commonly observed on the typical electrospray mass spectra produced by Janoshik and its analogues. If the only observed mass corresponds to a fragment with a missing residue or an alternative truncated sequence, the synthesis is impure.

3. The verification key on the COA matches the issuing lab’s portal

Every Janoshik certificate carries a short alphanumeric verification key. That key, together with the task ID printed on the certificate, can be cross-referenced on Janoshik’s public-records portal. A real BPC-157 batch will resolve. A fabricated COA will not. If you do not have a verification key on the certificate at all, treat it as an unverified document.

Storage and handling at your bench

Refrigerate at 2–8 °C in the original sealed amber-glass vial. BPC-157 is stable for 24 months or more in the lyophilised state when kept dry, sealed, and protected from light.
Reconstitute with bacteriostatic water by adding the water slowly down the inside wall of the vial and gently swirling (not shaking) until the cake fully dissolves. The resulting solution should be visually clear and colourless.
Reconstituted shelf life is shorter than the lyophilised form. The published preclinical analytical literature commonly references stability over a window of two to three weeks under refrigeration; consult the specific assay or research method you are running for the exact figure for your context.
Avoid freeze-thaw cycles on the reconstituted solution. Repeated freezing and thawing is the single most common reason a previously good vial of any reconstituted research peptide drops in measurable activity over time.

Common red flags when sourcing

Walk-away signals when buying BPC-157

The lyophilised cake in the supplier’s product photos is yellowed, off-colour, or shown as a heap of loose granules rather than a uniform porous white cake. Freeze-drying done correctly produces a solid puck, not a powder.
No batch-specific Certificate of Analysis included with the order. A generic “we test our products” statement on the supplier’s website is not the same as a per-batch COA tied to the vial in your hand.
The COA carries no verification key, or the key does not resolve on the issuing lab’s public portal. A real Janoshik certificate is independently verifiable; a fabricated one is not.
Mass-spectrometry data is absent and the only quoted purity figure is a percentage on a results table, with no chromatogram and no MS spectrum to underwrite it. Numbers without traces are not evidence.
The supplier markets BPC-157 oral capsules with strong claims about “gut-healing” or systemic effects after oral administration. Even given the unusual gastric stability of the molecule, this kind of claim is outside the published preclinical literature and outside the research-reagent supply category we operate in.
Pricing is far below the broader market rate. BPC-157 is not the cheapest peptide to synthesise correctly to 99%+ purity. A vial advertised at a quarter of the market rate is, more often than not, a vial of something else.
The supplier ships BPC-157 in clear glass with no temperature-controlled packaging in summer months, or has no batch numbering visible on the vial label.

Where this fits in the wider picture

BPC-157 sits in the regenerative-research family alongside TB-500, GHK-Cu, and Thymosin Alpha-1. The four are different chemistries serving overlapping research contexts, and the right choice in any given lab setting depends on which mechanism the assay is asking about. Our side-by-side write-ups cover the trade-offs:

BPC-157 vs TB-500 – pentadecapeptide vs Thymosin Beta-4 fragment
GHK-Cu vs BPC-157 – copper tripeptide vs pentadecapeptide

The KLOW research blend in our catalogue includes BPC-157 as one of its four components alongside GHK-Cu, TB-500, and KPV. KLOW is a single research-context tool that combines the four; if the work being run only calls for one of the four, the standalone single-peptide vial is the simpler reference choice.

What we supply

We stock BPC-157 as a lyophilised cake in 10mg amber-glass vials, independently HPLC-verified by Janoshik Analytical to 99%+ purity. The Janoshik Certificate of Analysis ships in the box with every order where one is available for the current batch, and the report is also published on our Purity page for independent reference. The product page with current pricing, the integrated dose calculator, the research-protocol tabs, and the BAC-water option is at /peptides/bpc157.html.

Research use only. The compound information described above is drawn from peer-reviewed analytical and preclinical literature and is provided for laboratory and in-vitro research context. Pure Peptides Lab Ltd does not provide therapeutic claims, dosing guidance, administration protocols, or any content relating to human or veterinary use. Researchers operating adjacent to a competitive sport context should additionally consult the current WADA Prohibited List directly, since that list is updated annually and BPC-157’s status is a moving target across recent revisions.

BPC-157: the most-researched peptide in the catalogue