TB-500 5mg Vial | Thymosin Beta-4 Fragment

TB-500 supplied as 5 mg of lyophilised powder in a sealed vial. An acetylated seven-residue fragment corresponding to residues 17 to 23 of thymosin beta-4, molecular weight 889.0 g/mol.

Read this before ordering: TB-500 is not thymosin beta-4

Two chemically different substances are sold across this market under the same name, and the difference is not marginal.

TB-500 is the acetylated seven-residue fragment, Ac-LKKTETQ, at 889.0 g/mol. Thymosin beta-4 is the full naturally occurring protein of 43 residues, at approximately 4,963 g/mol — five and a half times the mass. They are not interchangeable, they do not behave identically, and a certificate of analysis for one does not describe the other.

This product is the fragment. The molecular weight on the certificate of analysis is the way to verify which one you have actually received, from us or from anyone else. If a supplier will not state the mass, that is the question to press.

What the fragment does in the literature

Thymosin beta-4 is an actin-sequestering protein involved in cytoskeletal organisation and cell migration, both of which matter to wound closure. The 17-23 region contains the actin-binding motif, which is why this particular fragment was synthesised and studied rather than an arbitrary section of the protein.

An important asymmetry in the evidence: full-length thymosin beta-4 has been through human clinical trials in several indications. The seven-residue fragment sold as TB-500 largely has not. Literature describing the full protein should not be read as describing this fragment.

Supplied as a single compound

TB-500 is often sold blended with BPC-157. We supply the two separately. A fixed-ratio blend gives results that cannot be attributed to either component, which makes it unsuitable for research even where it is commercially convenient.

Price per milligram

This vial is £32.99 for 5 mg, which is £6.60 per milligram. Comparing suppliers on price per milligram rather than headline price is the only like-for-like comparison, because vial strengths are not standardised across this market.

Does it come with a certificate of analysis?

Every batch is supplied with a certificate of analysis stating the batch reference, identity confirmation, chromatographic purity against specification, and the analytical method used. Purity is determined by reverse-phase HPLC with mass spectrometric identity confirmation. The certificate is specific to the batch you receive rather than a generic sample document, and states the laboratory that performed the work.

How is it reconstituted?

Vials arrive as a lyophilised cake under vacuum. Store sealed at −20 °C, protected from light. Allow the vial to reach room temperature before breaking the seal, which prevents condensation drawing moisture into the powder.

Reconstitute with bacteriostatic water added slowly down the vial wall. Swirl gently until the cake has fully dissolved; the solution should be clear and colourless.

Once in solution, TB-500 should be kept refrigerated at 2 to 8 °C and protected from light. Avoid repeated freeze-thaw cycles, which degrade peptides faster than steady refrigeration. Reconstituted material is not indefinitely stable and working solutions are best prepared in the volumes actually needed.

Cold chain and UK dispatch

Held at −20 °C from arrival through to dispatch. Orders ship in insulated packaging with a cold pack, tracked, so material spends as little time as possible at ambient temperature. Short transit excursions are normal for lyophilised peptides and do not compromise a sealed vial, but the powder should go back into cold storage on arrival.

Supplied strictly for laboratory research use only. Not for human or veterinary use, and not for diagnostic or therapeutic application. Purchasers must be 18 or over and are responsible for compliance with the rules applying to them.