What TB-500 is
TB-500 is a synthetic peptide corresponding to the actin binding region of thymosin beta 4, a protein present in most human cell types and in wound fluid. The full protein is 43 amino acids; TB-500 reproduces the short active sequence rather than the whole molecule, which is why it can be synthesised chemically and supplied in solution.
How the pen is supplied
Solution in a sealed 2 ml pen graduated in 200 dial units. Frequently held alongside BPC-157, which is why the two appear together in most searches.
Pen specification
| Class | Synthetic fragment of thymosin beta 4 |
| Also known as | Thymosin Beta 4 fragment, TB4 frag |
| Content | 10 mg |
| Fill volume | 2 ml |
| Dial graduation | 0.01 ml per unit |
| Total dial units | 200 |
| Per dial unit | 50 mcg |
| Cost per mg | £5.50 per mg |
Milligrams per dial unit and cost per milligram are calculated from the pen strength, its fill volume and the current live price. Every SerenQ pen is graduated at 0.01 ml per unit.
Verification
Independent HPLC per batch, batch identifier printed on the unit.
- SerenQ TB500 10mg Peptide Penin stock£55
Availability checked 2026-09-04. The product page carries live stock.
Common questions
Is TB-500 the same as thymosin beta 4?
No. Thymosin beta 4 is the full 43 amino acid protein. TB-500 is a short synthetic fragment of it, covering the actin binding region.
Why is it usually listed next to BPC-157?
The two are commonly researched together in the same connective tissue models, so demand for one tracks the other closely.