Buy Thymosin Beta-4 Research Peptide

Thymosin Beta-4 (CAS 77591-33-4), also designated Tβ4 or TB4, is a synthetic 43-amino acid polypeptide with the molecular formula C₂₁₂H₃₅₀N₅₆O₇₈S and a molecular weight of 4963.44 g/mol. Its full sequence — Ac-Ser-Asp-Lys-Pro-Asp-Met-Ala-Glu-Ile-Glu-Lys-Phe-Asp-Lys-Ser-Lys-Leu-Lys-Lys-Thr-Glu-Thr-Gln-Glu-Lys-Asn-Pro-Leu-Pro-Ser-Lys-Glu-Thr-Ile-Glu-Gln-Glu-Lys-Gln-Ala-Gly-Glu-Ser — features an N-terminal acetylation and belongs to the beta-thymosin family, a class of 16 highly conserved actin-sequestering peptides first isolated from calf thymus tissue. Tβ4 is one of the most abundant intracellular peptides in mammalian nucleated cells, with concentrations ranging from 0.1 to 0.5 mM in most cell types. Produced via solid-phase peptide synthesis, Thymosin Beta-4 acts as the principal G-actin sequestering protein in the mammalian cytoplasm and is one of the most extensively studied cytoskeletal regulatory peptides in preclinical cell biology.

Thymosin Beta-4 is investigated across an exceptionally broad range of preclinical research contexts, reflecting the ubiquitous expression of Tβ4 across nearly all mammalian cell types and tissues. The compound's interaction with monomeric G-actin — mediated through its central LKKTETQ motif (residues 17-23) and the WH2 (WASP homology 2) domain — regulates the actin monomer pool available for F-actin polymerization, placing Tβ4 at the nexus of cell migration, morphogenesis, and cytoskeletal dynamics. Published in vitro studies have characterized the Tβ4-actin interaction at the structural level through NMR and X-ray crystallography, revealing a 1:1 stoichiometric complex in which Tβ4 extends along the cleft between actin subdomains 1 and 3, sequestering the monomer in an unpolymerizable state. In vivo rodent studies have investigated Thymosin Beta-4 in cardiac ischemia-reperfusion models, with published research examining coronary vessel formation, cardiomyocyte survival signaling through the Akt/PKB pathway, and the compound's interaction with the epicardial progenitor cell population — a research context distinct from the dermal wound and corneal injury models more commonly associated with its synthetic counterpart TB-500.

Thymosin Beta-4 is manufactured in an ISO9001 certified laboratory to a guaranteed purity of 98% or above. Every batch is independently tested using HPLC and MS-UPLC analysis before dispatch. Vials are vacuum sealed and stored in a temperature controlled, monitored cold storage system to preserve compound integrity throughout the supply chain. Certificates of Analysis are available to view and download directly on the product page.

Sold strictly for in vitro research purposes only. Not for human consumption. Intended for use by qualified researchers in laboratory settings only.

Scientific Review

Dr. Martina Rossi, PhD

Scientific Contributor and Reviewer

Reviewed for scientific accuracy, 14 June 2026

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