Molecular Structure Explorer
BPC-157
Compounds covered in this guide are shown first.
Last reviewed: October 2026 · Cleared Peptides research team
Research use only. BPC-157 vs TB-500: Research Comparison is supplied for laboratory research. It is not a drug, food, cosmetic, or dietary supplement. It is not FDA-approved. It is not for human or veterinary administration. This page does not give a dose or a method of administration. A study cited on this page describes that study’s own test article. It does not make this lot an approved medicine. To check a fact, open the PubMed or DOI link, confirm the authors and year, and match the paper’s compound name, CAS number, or sequence to the specification table. The full method is on the research desk page. Identity and purity for a lot are only what that lot’s certificate of analysis reports. An HPLC percentage is not a sterility result and not an endotoxin result unless the certificate prints those tests.
BPC-157 and TB-500 are two of the most frequently researched peptides and are often studied together. They are, however, very different molecules. This page compares them using published structural and in-vitro data.
Side-by-Side Comparison
| BPC-157 | TB-500 (Thymosin Beta-4) | |
|---|---|---|
| CAS | 137525-51-0 | 77591-33-4 |
| Formula | C62H98N16O22 | C212H350N56O78S |
| MW (g/mol) | ≈1419.5 | ≈4963.4 |
| Length | 15 aa | 43 aa (N-acetylated) |
| Origin | Fragment of a gastric-juice protein | Endogenous actin-sequestering peptide |
| Main in-vitro research areas | Cell migration, NO and growth-factor receptor signaling | Actin dynamics, cell migration, angiogenesis signaling |
| Research product | BPC-157 | TB-500 |
Why Researchers Pair Them
Because the two peptides act through unrelated mechanisms — growth-factor/NO signaling for BPC-157 and actin sequestration for Tβ4 — they are commonly examined side by side in cell-migration and cytoskeletal models. For combination studies Cleared Peptides offers a pre-combined BPC-157 + TB-500 blend, plus the GLOW (adds GHK-Cu) and KLOW (adds GHK-Cu and KPV) blends.
Detailed guides: BPC-157 · TB-500.
Research materials referenced in this guide
Analytical testing notes for BPC-157 vs TB-500
BPC-157 vs TB-500 is identified in this guide. An identity test compares a measurement with those values. A mass spectrum is the usual measurement for a peptide. FTIR, when a certificate uses it, is a supporting infrared fingerprint and is less specific for closely related sequences.
This page compares more than one component. A single purity percentage is ambiguous unless the certificate says whether each component was resolved, identified, and quantified. Identity and content should be traceable to each named material. A chromatogram with several intentional peaks is expected; those peaks are not automatically impurities.
HPLC purity for this material is an area-percent result at the wavelength and gradient the laboratory states, commonly ultraviolet detection near 214 nm on a reversed-phase column. The instrument is a gradient pump, injector, column oven, and UV or diode-array detector. That percentage is not the number of milligrams in the vial. Water, acetate, trifluoroacetate, and other UV-silent material can dominate the gross weight while the purity figure stays high. Net peptide content, from an assay or amino-acid analysis, is the separate result to read when the certificate reports it.
A sterility test and an endotoxin test are not included in a chemical purity result. The compendial sterility test is a culture method (USP <71>): membrane filtration or direct inoculation into fluid thioglycollate medium and soybean-casein digest medium, incubated for 14 days. A PCR sterility screen uses a thermal cycler to detect microbial DNA and is a different method. The endotoxin test (USP <85> LAL, or USP <86> recombinant Factor C) reports endotoxin units with an incubating reader or a cartridge reader. Use a result only when that method is printed on the lot certificate. One published example in this catalog states that the report does not cover microbial contamination or endotoxins. The full description of equipment, standards, and how US laboratory accreditation works is in peptide analytical testing. Lot records are on the COA page.
Frequently Asked Questions
Is BPC-157 the same as TB-500?
No. BPC-157 is a 15-residue gastric-protein fragment; TB-500 is the 43-residue Thymosin Beta-4.
Can I buy BPC-157 and TB-500 together?
Yes, as a pre-combined research blend for laboratory use only.
Written by the Cleared Peptides Research Desk, the editorial desk of Cleared Wellness Group LLC. This is not a personal profile of a physician or a scientist, and it is not a fictional author. The checking method is public on the research desk page. Last reviewed October 2026.
Comparing the evidence, not the nicknames
Research use only. BPC-157 and thymosin β4 are separate laboratory materials. This comparison is not a dose, a stack, or a method of administration.
They are easy to confuse only at the nickname layer. Chemically they do not overlap. BPC-157 is Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val, about 1419.5 g/mol, CAS 137525-51-0. The TB-500 specification on this site is acetylated thymosin β4, 43 residues, about 4963.4 g/mol, CAS 77591-33-4, not the LKKTETQ fragment.
The evidence shapes are also different. BPC-157’s experimental papers and the reviews used here (Seiwerth 2018, PubMed 29998800; Seiwerth 2021, PubMed 34267654) come largely from one group. That concentration is a reason to read the methods, not a reason to invent a contrary clinical claim. Thymosin β4 has a clearer biochemical anchor: Safer, Elzinga, and Nachmias showed it is the actin-sequestering peptide Fx (PubMed 1999398). Goldstein, Hannappel, and Kleinman’s 2005 review then discusses injury models (PubMed 16099219). A tissue-repair sentence in a review is not an identity test, and it is not evidence about a blend.
A laboratory comparison uses two masses, two chromatograms, and two certificates. It does not use one shared story.
Selected References
Peer-reviewed literature on the compounds discussed in this guide, listed as scientific background for laboratory researchers. Citation does not imply endorsement by the authors or any use other than in-vitro research.
- Sikiric P, et al. Stable gastric pentadecapeptide BPC 157-NO-system relation. Curr Pharm Des. 2014;20(7):1126-35. PubMed 23755725 · DOI
- Sikiric P, et al. Brain-gut Axis and Pentadecapeptide BPC 157: Theoretical and Practical Implications. Curr Neuropharmacol. 2016;14(8):857-865. PubMed 27138887 · DOI
- Nachmias VT. Small actin-binding proteins: the beta-thymosin family. Curr Opin Cell Biol. 1993;5(1):56-62. PubMed 8448031 · DOI
- Dedova IV, et al. Thymosin beta4 induces a conformational change in actin monomers. Biophys J. 2006;90(3):985-92. PubMed 16272441 · DOI
Laboratory note: solubility depends on salt form and solvent. This guide does not state a single solubility figure. Handling of lyophilized material is described in the peptide storage guide.
Research Use Only Notice
This guide is provided for educational and laboratory reference purposes. It summarizes published, primarily in-vitro and structural research literature and does not describe, recommend or imply any use in humans or animals. Products sold by Cleared Peptides are for laboratory research use only; they are not drugs, foods, cosmetics or dietary supplements, are not FDA-approved, and are not intended to diagnose, treat, cure, mitigate or prevent any disease. No dosing, administration or therapeutic information is provided.
