Fragment vs. full-length: TB-500 is a synthetic fragment of Thymosin Beta-4 — di

Fragment vs. full-length: TB-500 is a synthetic fragment of Thymosin Beta-4 — di

Vial comparison: understanding the difference between TB-500 fragment and full-l

Vial comparison: understanding the difference between TB-500 fragment and full-l

Two different molecules share the shop name “TB-500.” Full-length thymosin β4 is a 43-residue actin-binding peptide, often indexed CAS 77591-33-4. This catalog’s TB-500 line is a fragment listing: Ac-LKKTETQ, CAS 885340-09-2. Putting the 43-aa sequence on our vial page would be a mislabel.

RUO. Laboratory reagent listing. Not for human or veterinary use. Not a medicine, food, cosmetic, or supplement. Lot HPLC, MS, and net peptide content, when issued, live on the lot COA — we do not invent a percentage on this page.

Side by side

This catalog’s TB-500Thymosin β4 (full)
CAS885340-09-277591-33-4 (commonly indexed)
Identity lineAc-LKKTETQ43-aa Tβ4 (SDKP… at the N-terminus in the native protein)
What MS must matchheptapeptide fragment mass~4963 Da class (salt form aside)

A COA that quotes 77591-33-4 against a fragment vial is the wrong paper. Intact mass vs the sequence on the label is the check. Thymosin alpha-1 is a third, unrelated peptide: 28-residue N-acetyl Tα1.

We do not invent HPLC% and we do not treat this reagent as an injury protocol. TB-500 catalog page. Earlier overview: TB-500 research note.

Knowing is not enough; we must apply. — Johann Wolfgang von Goethe

TB-500 listing

Fragment identity Ac-LKKTETQ. Not full Tβ4. Lot paper on request.

View TB-500 →

References

  1. Catalog identity for this site’s TB-500 SKU: CAS 885340-09-2, Ac-LKKTETQ, as printed on the product spec strip. Confirm observed mass on the lot COA.
  2. Thymosin β4 (full-length) is a separate 43-residue protein; do not copy that sequence onto a fragment listing.