TB-500 is a synthetic fragment corresponding to the active region (residues 17–23) of Thymosin β-4 — a 43-residue actin-sequestering peptide expressed throughout mammalian tissues. The research literature describes it as a principal mediator of Tβ-4's reported effects on cell migration, angiogenesis, and tissue repair. Supplied as lyophilized powder with 3rd-party HPLC verification and full COA per lot.
TB-500 is the commercial research designation for a synthetic fragment of Thymosin β-4 (Tβ-4), a 43-residue actin-sequestering peptide originally isolated from the bovine thymus in the early 1980s by Allan Goldstein's laboratory at George Washington University. The literature describes Tβ-4 as one of the most abundant polypeptides in mammalian cells, where it functions as the principal intracellular G-actin-sequestering protein.
The "TB-500" preparation sold as a research chemical historically refers to the N-acetylated heptapeptide fragment corresponding to Tβ-4 residues 17–23 (Ac-LKKTETQ). Published work identifies this short sequence as the minimal region retaining the reported cell-migration and tissue-repair activities characteristic of the full-length parent protein.
Tβ-4 and TB-500 are described in the literature as acting through multiple reported pathways. Published studies describe binding of G-actin monomers through the conserved LKKTETQ epitope, modulation of actin polymerization and cell motility, and reported effects on endothelial cell migration and tube formation (angiogenesis). Additional reported activities include upregulation of VEGF and modulation of matrix metalloproteinases (MMPs) implicated in tissue remodeling.
TB-500 carries a distinctive regulatory history: the compound has been studied extensively in equine veterinary research, particularly for reported effects on tendon and soft-tissue recovery in racehorses. This application history — along with a widely cited body of preclinical mammalian research — accounts for much of the research interest in the compound.
TB-500 is not an FDA-approved drug for any indication and is not approved for human use. In 2011, the World Anti-Doping Agency (WADA) added Thymosin β-4 to the prohibited list (S2 class — peptide hormones, growth factors, and related substances) for competitive sport. The compound is widely available as a research chemical.
Supplied as a white to off-white lyophilized powder. Reported solubility is in bacteriostatic water or sodium chloride 0.9%. Reported serum half-life following parenteral administration is approximately 2–3 hours; the lyophilized form is reported stable at 2–8°C for extended periods, with reconstituted solution stable under refrigeration for several weeks.
The above summarizes published research literature. This is not medical advice, a protocol, or a recommendation for use. This compound is supplied for laboratory research only.
Every lot is tested by an independent 3rd-party analytical laboratory before release. The standard analytical panel includes reverse-phase HPLC (minimum 99.5% release spec, typically >99.9%), mass spectrometry for identity confirmation, Karl Fischer for water content, LAL assay for endotoxin (<0.25 EU/mL), bioburden, and sterility testing per USP <71>.
The resulting Certificate of Analysis PDF is attached to every order and is lookup-able by lot number after the fact.
They are structurally unrelated compounds often grouped together in the research literature because they are both studied in tissue-repair contexts. TB-500 is a synthetic fragment of Thymosin β-4 — a 43-residue actin-sequestering protein — with reported activity related to actin binding and cellular migration. BPC-157 is a 15-amino-acid pentadecapeptide originally identified in gastric juice with a different proposed mechanism.
In the research literature they are frequently studied alongside one another. They are different molecules with different reported targets, different molecular weights (TB-500 ~4,965 Da vs BPC-157 ~1,420 Da), and different regulatory histories. The frequent pairing is a function of their shared research context, not structural similarity.
The two peptides have been the subject of combination-use discussion in the preclinical and gray-literature landscape, but from a chemistry standpoint they share essentially no structural similarity.
Shipped at ambient temperature in discreet, tamper-evident packaging. Lyophilized peptide powder is stable at room temperature for typical transit windows, which is why research-grade vendors ship this way without cold-chain logistics. Tracked via carrier; signature not required.
Upon receipt, store the unopened lyophilized vial refrigerated at 2–8°C and protected from light. Literature reports the lyophilized form is stable for up to 24 months under these conditions. If reconstituted per published solubility data, the solution is typically stable for several weeks at 2–8°C. Do not freeze.
TB-500 is a synthetic heptapeptide fragment corresponding to residues 17–23 of Thymosin β-4, with N-terminal acetylation. The active fragment sequence is Ac-LKKTETQ. The commercial "TB-500" research preparation has a molecular formula of C212H350N56O78S and a molecular weight of approximately 4,965 Da.
Supplied as a white to off-white lyophilized powder. The full primary structure and reference data are in the Compound Profile section above.
Supplied as a white to off-white lyophilized powder. The full primary structure is in the Compound Profile section above.
All compounds are synthesized by qualified partner laboratories operating under standard peptide synthesis practices. Synthesis records, raw material provenance, and release testing are documented in the lot file.
Each lot is independently verified by a 3rd-party analytical lab — not our in-house testing — before release. The COA PDF identifies the release lab, the method, and the analyst.
Domestic US shipping to all 50 states via USPS / UPS. Tracking provided at dispatch. International shipping is evaluated on a case-by-case basis due to jurisdictional import regulations.
All products offered on this site are intended for laboratory research purposes only. They are not for human consumption, oral ingestion, or any form of in-vivo use in humans or animals. These compounds are not medicines or drugs and have not been approved by the FDA to prevent, treat, or cure any medical condition, ailment, or disease.
By placing an order you acknowledge that you are a qualified researcher over the age of 21 and that you assume all responsibility for handling, storage, and end use of the compounds in accordance with applicable law.
HPLC-verified. Mass-spec confirmed. Ambient-stable transit. The paperwork other vendors hope you never ask for.
⚠ ALL PRODUCTS ARE INTENDED FOR LABORATORY RESEARCH PURPOSES ONLY. NOT FOR HUMAN CONSUMPTION, ORAL INGESTION, OR ANY FORM OF IN-VIVO USE IN HUMANS OR ANIMALS. THESE COMPOUNDS ARE NOT MEDICINES OR DRUGS AND HAVE NOT BEEN APPROVED BY THE FDA. BY PLACING AN ORDER YOU ACKNOWLEDGE YOU ARE A QUALIFIED RESEARCHER OVER THE AGE OF 21.