TB-500

Purity & Laboratory Testing

• Purity: Reversed-phase HPLC-verified ≥99%.
• Identity: Confirmed by mass spectrometry (MS) against the expected molecular mass of the acetylated heptapeptide sequence.
• Sequence: Ac-Leu-Lys-Lys-Thr-Glu-Thr-Gln (Ac-LKKTETQ), corresponding to Tβ4 residues 17–23, as characterized on the lot COA.
• CAS / molecular formula: not disclosed for this fragment; lot-specific analytical values are reported on the COA.
• Documentation: A lot-specific Certificate of Analysis (COA) accompanies each batch.

These figures describe analytical characterizations of identity and purity only and do not imply any biological or therapeutic property. For research use only, not for human use.

A Certificate of Analysis is available per production lot, documenting HPLC purity and mass-spectrometry identity confirmation.

View Certificates of Analysis →

For Research Use Only · Not for human or veterinary use · Not for diagnostic or therapeutic use.

References to clinical phases/studies describe the compound in independent third-party literature (e.g., ClinicalTrials.gov, PubMed) and do not represent claims, testing, or approval by Zynix Biolab.

Research Background & Study Phase

TB-500 is a synthetic, N-terminally acetylated heptapeptide (Ac-LKKTETQ) corresponding to the actin-binding domain (residues 17–23) of thymosin beta-4 (Tβ4), a 43-amino-acid member of the beta-thymosin family of actin-sequestering peptides. The parent Tβ4 molecule has been characterized in the literature as forming a 1:1 complex with monomeric (G-)actin and inhibiting its polymerization, a mechanism examined extensively in cell-biology research (e.g., Cassimeris et al., J. Cell Biol. 1992; Yu et al., J. Biol. Chem. 1993).

In third-party research, the full-length Tβ4 molecule (formulated as the investigational ophthalmic candidate RGN-259) has been the subject of registered clinical studies, including a Phase 2 dry-eye trial (ClinicalTrials.gov NCT01393132) and a Phase 3 neurotrophic keratitis trial (ClinicalTrials.gov NCT02600429). These registry entries describe research on the parent Tβ4 peptide by independent sponsors and are provided here only as scientific context.

For Research Use Only · Not for human or veterinary use · Not for diagnostic or therapeutic use.

Research Applications

In published third-party literature, thymosin beta-4 and its actin-binding fragment have been investigated in in-vitro and laboratory model systems exploring lines of inquiry that include:

• Actin monomer (G-actin) sequestration and inhibition of actin polymerization.
• Cytoskeletal dynamics and in-vitro models of cell migration.
• Angiogenesis-related signaling and endothelial cell behavior in cell-culture models.
• Tissue-repair and wound-closure pathways studied in preclinical animal and in-vitro models.

These research directions are provided for scientific context only and reflect work reported by independent investigators. This product is not for human use, diagnostic use, or therapeutic use.

Handling, Storage & Reconstitution

• Storage (lyophilized): Store the lyophilized powder at -20°C, protected from light and moisture.
• Reconstitution: For laboratory preparation, reconstitute with bacteriostatic or sterile water and gently swirl (do not shake) until fully dissolved.
• Post-reconstitution: Keep refrigerated (2–8°C) and protect from repeated freeze-thaw cycles; aliquot to minimize degradation.
• PPE: Handle with appropriate personal protective equipment (gloves, lab coat, eye protection) under standard laboratory practice.

This information describes laboratory handling of a research material and is not a dosing or administration instruction. For research use only — not for human use.

For Research Use Only · Not for human or veterinary use · Not for diagnostic or therapeutic use.

Scientific References

• Cassimeris L, et al. Thymosin beta 4 sequesters the majority of G-actin in resting human polymorphonuclear leukocytes. J Cell Biol. 1992. PMID: 1447300.
• Yu FX, et al. Actin-sequestering ability of thymosin beta 4, thymosin beta 4 fragments, and thymosin beta 4-like peptides as assessed by the DNase I inhibition assay. J Biol Chem. 1993. PMID: 8471179.
• Sosne G, et al. Thymosin β4 significantly improves signs and symptoms of severe dry eye in a phase 2 randomized trial. Cornea. 2015. PMID: 25826322.
• ClinicalTrials.gov: NCT02600429 (Phase 3, thymosin β4 / RGN-259, neurotrophic keratitis).

These references are provided for scientific context only and are not claims by Zynix Biolab.