TB-500 research guide
Synthetic N-acetylated fragment associated with thymosin beta-4
An identity-focused guide explaining why TB-500 should not be treated as a synonym for full-length thymosin beta-4 and what analytical studies actually found.
AUS Peptide Supply editorial team01 · Identity
What the name identifies
Published analytical work identified TB-500 material as the N-terminally acetylated seven-residue sequence Ac-LKKTETQ, corresponding to residues 17–23 of thymosin beta-4. Full-length thymosin beta-4 contains 43 amino acids. Treating the fragment and full protein as interchangeable can misstate both identity and evidence.
02 · Evidence position
What the literature can support
Much of the directly relevant literature concerns analytical detection and animal anti-doping work, not controlled human efficacy. Biological findings for full-length thymosin beta-4 cannot automatically be assigned to the shorter TB-500 fragment. The TGA lists TB-500 among unapproved peptide products of concern.
03 · Study-level map
Evidence and its limits
What has been identified as TB-500?
High-resolution mass-spectrometry research identified an N-acetylated 17–23 thymosin beta-4 fragment in a product sold as TB-500.
Limit: Identification of one marketed product does not prove every TB-500-labelled batch has the same composition.
What newer biological evidence exists for the fragment?
A 2024 study examined TB-500 metabolism in vitro and in rats and compared parent and metabolite activity in a cell assay.
Limit: The authors noted that biological effects of TB-500 itself had not been documented previously; rat and cell findings are not human efficacy evidence.
What is the Australian context?
The TGA identifies TB-500 in current warnings about unapproved peptides.
Limit: A research-only label does not resolve legal status or make public therapeutic promotion lawful.
04 · Analytical context
Questions a batch record should answer
- 01Does the expected mass correspond to Ac-LKKTETQ rather than full-length thymosin beta-4?
- 02Are non-acetylated, truncated and metabolite-like species resolved by the method?
- 03For blends, is each component identified and quantified independently instead of assigning one total-purity result?
05 · Boundary conditions
What this record does not establish
- Full-length thymosin beta-4 evidence is not automatically TB-500 evidence.
- The directly relevant human efficacy evidence is not established by the cited analytical work.
- This page makes no tissue-repair or performance claim.
Sources checked
- 1.Synthesis and characterization of the N-terminal acetylated 17-23 fragment identified in TB-500
PubMed / Drug Testing and Analysis · 2012 · Primary study
- 2.Simultaneous quantification of TB-500 and its metabolites
PubMed / Journal of Chromatography B · 2024 · Primary study
- 3.Concerns regarding public health risks associated with unapproved peptide products
Therapeutic Goods Administration · 2026 · Regulator