Description
Thymosin Beta-4 Fragment 1-4 is the four-amino-acid N-terminal piece of Thymosin Beta-4, better known in the literature as Ac-SDKP. Limitless Life Nootropics supplies it in 5mg and 10mg vials, made in the USA and independently tested.
What Is Thymosin Beta-4 Fragment 1-4?
Ac-SDKP (N-acetyl-seryl-aspartyl-lysyl-proline) is released naturally when the full Thymosin Beta-4 protein is cleaved by the enzyme prolyl oligopeptidase. It circulates in plasma and is broken down by angiotensin-converting enzyme (ACE), which is why its levels rise in experimental models that use ACE inhibitors.
This small peptide has developed its own body of research, separate from the full-length protein. Investigators have studied it as an anti-fibrotic and anti-inflammatory agent in models of heart, kidney and lung fibrosis, as well as a regulator of hematopoietic stem cell proliferation.
Its short length makes it easy to characterize analytically, and its well-defined biology makes it a useful tool when researchers want to separate the effects of the N-terminal region from the actin-binding activity of the whole molecule.
Research Applications
Published preclinical work has examined this peptide across several areas of investigation:
- Cardiac and renal fibrosis models
- ACE inhibitor and Ac-SDKP interaction studies
- Hematopoietic stem cell regulation
- Macrophage and inflammatory cytokine research
- Angiogenesis in endothelial cell cultures
Researchers can review peer-reviewed studies on Ac-SDKP through the National Library of Medicine (PubMed) database.
Thymosin Beta-4 Fragment 1-4 Specifications
| Product | TB-500 Thymosin Beta-4 Fragment 1-4 |
|---|---|
| Compound type | N-acetylated tetrapeptide (Ac-Ser-Asp-Lys-Pro) |
| Available sizes | 10mg, 5mg |
| Format | Lyophilized (freeze-dried) powder in a sealed glass vial |
| Purity | ≥99% (HPLC verified) |
| Origin | Manufactured in the USA |
| Testing | Independent third-party lab |
| Intended use | Laboratory research only |
The Limitless Life Nootropics Standard
Independent researchers, university groups and private laboratories rely on Limitless Life Nootropics for consistent quality and responsive service. Every listing includes accurate format and size information, our compounds are stored under controlled conditions until they ship, and we stand behind every order. If something is not right, our U.S.-based support team will make it right.
Quality and Third-Party Testing
Every batch of this peptide sold by Limitless Life Nootropics is produced in the United States and verified by an independent third-party laboratory. Testing includes HPLC purity analysis and mass spectrometry identity confirmation, and a certificate of analysis is available for each lot so researchers can document exactly what they are working with.
Storage and Handling of Thymosin Beta-4 Fragment 1-4
Store the sealed vial of this peptide at -20°C (-4°F) for long-term stability, away from light and moisture. Once reconstituted, keep the solution refrigerated at 2–8°C and use it within the window defined by your laboratory protocol.
Need supplies? Pair your order with our reconstitution solution and sterile 10 mL vials for convenient preparation.
Ordering and Shipping
We know research timelines are tight. Most orders ship within one to two business days from our U.S. facility, packed discreetly and tracked from dispatch to delivery. Checkout is encrypted, and our support team can help with documentation, order status or bulk quantities for ongoing projects.
Related Research Products
Teams working with this peptide often explore TB-500 (Thymosin Beta-4), TB-500 Thymosin Beta-4 Fragment 17-23 and BPC-157. Browse the full Cardiovascular Research and Musculoskeletal Research collections, or view every compound in our research peptide catalog at Limitless Life Nootropics.
Frequently Asked Questions
What is Ac-SDKP?
Ac-SDKP is the N-acetylated tetrapeptide Ser-Asp-Lys-Pro, the first four amino acids of Thymosin Beta-4.
How does it differ from TB-500?
TB-500 is the full 43-amino-acid protein, while this fragment is a 4-amino-acid piece with its own distinct anti-fibrotic research profile.
Is Thymosin Beta-4 Fragment 1-4 for human use?
No. It is sold strictly for laboratory research. It is not intended for human or animal consumption, diagnosis or treatment.
Where can I buy Thymosin Beta-4 Fragment 1-4 online?
You can order it directly from Limitless Life Nootropics, a U.S. supplier of third-party tested research peptides with fast, discreet shipping.
Research Use Only
All products sold by Limitless Life Nootropics are intended strictly for in-vitro laboratory research and scientific study. This product is not a drug, food, supplement or cosmetic, has not been evaluated by the FDA, and is not for human or veterinary use. Purchase is limited to qualified researchers aged 21 and over.








Reviews
There are no reviews yet.