Description
Structure & Identity
TB-500 is synthetic thymosin beta-4, the full 43-residue, N-terminally acetylated peptide. Its central LKKTETQ region carries the protein’s actin-sequestering activity. That region is why TB-500 is studied for actin regulation, cell migration, and cytoskeletal dynamics.
Research Background
Research on TB-500 draws on thymosin beta-4’s role in cell movement and actin regulation.
- Cell migration. As an actin-sequestering protein, thymosin beta-4 supports the cell migration that underpins tissue signaling, documented in foundational research [1].
- Multifunctional actin regulation. It is described in reviews as an actin-regulating peptide acting across several tissue-signaling processes [2].
- Active-region mapping. Work mapping thymosin beta-4’s activity onto its LKKTETQ region explains why that sequence is the focus of actin research [3].
These describe research areas, not approved uses, and the peptide is provided for laboratory study.
Specifications
| Attribute | Value |
| Chemical name | TB-500 (thymosin beta-4, full length) |
| Also Known As | Thymosin Beta-4, Tβ4 |
| CAS number | 77591-33-4 |
| Molecular weight | 4963.55 Da |
| Length | 43 amino acids (acetylated) |
| Purity | ≥99% by reverse-phase HPLC |
| Identity | Confirmed by ESI mass spectrometry |
| Physical form | Lyophilized powder |
| Appearance | White to off-white solid |
| Quantity | 10 mg per vial |
| Storage | -20°C, protected from light |
| Solubility | Soluble in water/DMSO for assay preparation |
| Classification | Research use only |
Storage & Handling
Keep the unopened vial at -20°C, away from light, until needed. Once dissolved, store the solution at 2-8°C and use for your research within roughly two weeks. Let the vial reach room temperature before opening to limit condensation, and aliquot the prepared material so it is not frozen and thawed repeatedly.
Quality Assurance
Every lot of TB-500 clears independent quality control before release. Manufacturing follows research-grade standards, and purity by reverse-phase HPLC and identity by mass spectrometry are confirmed by outside laboratories, including Janoshik Analytical and US-based labs. A batch-matched certificate of analysis accompanies the vial so the data traces to your material.
Frequently Asked Questions
What is the TB-500 10 mg used for in research?
It is full-length synthetic thymosin beta-4, studied in cell-migration and actin-regulation research. TB-500 is a research-use-only material and is not approved for human or veterinary use.
Is the 10 mg the same as the 5 mg TB-500?
Yes, apart from the amount of peptide in the vial. The 10 mg size suits research needing more working material.
Is TB-500 the full thymosin beta-4 protein?
Yes. It is the full 43-amino-acid, N-terminally acetylated thymosin beta-4 sequence; its LKKTETQ region carries the actin-binding activity.
How does TB-500 relate to actin?
Thymosin beta-4 binds and sequesters actin, which helps regulate the cell movement involved in cytoskeletal remodeling. TB-500 is the full-length peptide that carries that activity, not a short fragment.
Is TB-500 FDA approved?
No, it is not FDA approved. It featured in the 2026 FDA compounding review but was not approved. This listing is a research-use-only reference peptide, not for human or veterinary use.
How should the 10 mg vial be handled?
Keep it frozen at -20°C and out of light. Once prepared for research, refrigerate at 2-8°C, aliquot, and use within about two weeks.
How is quality verified?
Purity is confirmed at ≥99% by reverse-phase HPLC with mass-spec identity confirmation by an independent lab, and a certificate of analysis is included with each batch.










