Research use only. The information below concerns laboratory reference materials for in-vitro research and makes no medical, therapeutic, diagnostic, cosmetic or performance claims.
“TB-500” is a commercial alias rather than an unambiguous sequence name. It is used inconsistently for Thymosin β4-related materials, so the label alone cannot identify a reference standard.
The fragment label
Fragment products sold as “TB-500” commonly identify the N-terminally acetylated heptapeptide Ac-LKKTETQ. The LKKTETQ sequence corresponds to residues 17-23 of Thymosin β4. A complete identity must state the exact sequence, terminal modifications, molecular formula and molecular weight rather than relying on the alias.
Full-length Thymosin β4
Full-length Thymosin β4 is a 43-amino-acid peptide with a substantially higher molecular weight. Some catalogues also apply the “TB-500” label to full-length material.
Why it matters for the lab
Because these materials differ in sequence and mass, a concentration calculated for one is incorrect for the other. Confirm which molecule the vial and source report identify before using a COA or mass-spectrometry result. The VERIPHASE BPC-157 + TB-500 blend is catalogued with a TB-500 fragment component; its exact terminal chemistry and measured identity must be confirmed by the released lot documentation.