BPC-157 Arginate

1 Identity

Sequence

The same pentadecapeptide as the BPC-157 record - H-Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val-OH, GEPPPGKPADDAGLV

Molecular formula

Peptide C62H98N16O22; article C62H98N16O22 · n C6H14N4O2, with n determined on every lot

Average mass

Peptide 1419.556 Da (C62H98N16O22). The article has no single average mass and cannot honestly be given one. L-arginine is C6H14N4O2, 174.204 Da, so the salt is: n=1, C68H112N20O24, 1593.760 Da, 89.07% net peptide; n=2, C74H126N24O26, 1767.964 Da, 80.29%; n=3, C80H140N28O28, 1942.168 Da, 73.09%; n=4, C86H154N32O30, 2116.372 Da, 67.07%. Four articles spanning 522.6 Da of formula weight and 22.0 percentage points of net peptide, all lawfully describable as 'BPC-157 arginate'. Stating one number for this SKU would be false; the number that goes on the label is net peptide in mg.

Monoisotopic mass

Peptide 1418.7042 Da; [M+H]+ m/z 1419.7115, [M+2H]2+ m/z 710.3594.

Salt / variant note

The variant problem here is STOICHIOMETRIC rather than structural, and it is unresolved in the market. Four articles differ by up to 522.6 Da and by 22.0 percentage points of net peptide across n = 1 to 4. A survey of live listings found not one seller stating an arginine-to-peptide ratio or a net peptide content: capsules at 500 mcg per capsule with the ratio undisclosed; capsules sold as 'Stable BPC-157 (Arginate Salt)' at 250 mcg per capsule with the capsule count not stated and the ratio undisclosed; 0.5 mg x 60 capsules sold as 'BPC-157 30 mg' with no arginate declaration at all; and 250 mcg capsules from a further seller. Beyond stoichiometry, the same-name substitution risk applies in full: the acetate and trifluoroacetate salts of the identical peptide are sold as 'BPC-157', at least one seller sells the arginate under the bare name, and no analytical method on an intact-mass certificate separates any of them. All backbone variants carried at the parent record apply here identically - C-terminal amide at -0.98 Da, des-Gly1 at -57.02 Da, N-acetyl at +42.04 Da, and the mass-silent Asp11-Gly13 isoaspartate. One further variant specific to this form: a lot that is trifluoroacetate-salt peptide with free arginine physically blended in would pass an arginine content test and is excluded only by the residual-TFA result.

2 Class & testing panel

Form

Single article

Testing panel

P1 — panel definition

3 Primary sources & evidence

The index reports the design and provenance of the literature, not a conclusion about effect.

No literature exists for the arginate as such. Every study identified - the rodent and in-vitro literature summarized in Vasireddi 2025 (systematic review) and McGuire 2025 (scoping review), Chang 2011 (rat Achilles and rat fibroblast culture), and the registered human trials NCT02637284 (Phase 1, oral, results not posted) and NCT07437547 (Phase 2, subcutaneous, Recruiting as at August 2026) - concerns the peptide without specifying a counterion. The claim implicit in the trade name 'Stable BPC-157 (Arginate Salt)' is a stability claim about a salt form, and no published stability comparison between the arginate and the acetate was identified.

4 Storage & specification

Storage

Lyophilized powder, -20 degrees C plus or minus 5 degrees C, sealed with in-pack desiccant under nitrogen, protected from light, handled below 30% relative humidity when open. The arginine salt exhibits higher hygroscopicity than alternative forms, affecting net peptide content when containers are opened. 2-8 degrees C acceptable for transit and for working stock held no longer than 30 days.

Shelf life

Provisional 24 months at -20 degrees C plus or minus 5 degrees C, assigned by protocol and only on clearance. Stability monitoring focuses on water content (Karl Fischer analysis), arginine molar ratio, and isoaspartate formation. Three-lot ICH Q1A protocol with a 6-month 25 degrees C / 60% RH accelerated arm.