TB-500 is a synthetic peptide corresponding to the naturally occurring protein thymosin beta-4 (Tβ4). The name is used inconsistently across the field — some suppliers apply it to full-length Tβ4 (43 residues), others to the short actin-binding motif Ac-LKKTETQ, which spans residues 17–23 of the parent protein and is a different molecule with a different mass. Read the certificate, not the name: the measured mass on the lot tells you which material you actually have. The peptide appears in pre-clinical research spanning cell biology, rodent models, and structure-activity relationship studies in published literature going back more than two decades.
This note describes the research context for TB-500 reference material. It does not make any claim about therapeutic use, medical benefit, dosing, or suitability for human or veterinary administration. Researchers working with TB-500 do so in analytical and in-vitro contexts.
Published research context
The research literature records investigations of TB-500 and the parent Tβ4 protein in:
- Cell migration assays
- In-vitro models of wound healing dynamics (cell culture, not organismal)
- Actin polymerization biochemistry (the primary published molecular mechanism of interest)
- Rodent models of tissue injury response
- Structure-activity relationship work across different peptide fragments of Tβ4
These studies are measurements of what happens in cell and animal models. They are not claims about clinical outcomes. The regulatory status of TB-500 in any major jurisdiction remains that of a research-use peptide, not an approved therapeutic.
What researchers use TB-500 reference standards for
Common research applications we see among our customers:
- Method development for peptide analytical chemistry labs building HPLC and LC-MS protocols.
- In-vitro cell work referencing published assay designs.
- Purity benchmarking for labs synthesizing their own TB-500 or analogs and needing a validated external reference.
- Stability and storage studies under varying buffer and temperature conditions, designed against the long-term, intermediate, and accelerated conditions in ICH Q1A(R2), with light exposure handled separately under ICH Q1B.
Every one of these is bench work. None involve human or animal administration of our reference standards.
Quality requirements for the lot you receive
Our TB-500 reference material ships with:
- Purity ≥ 99% by RP-HPLC, UV 214 nm detection
- Identity confirmed by ESI-MS against the published 4963.46 Da molecular mass
- Third-party analytical certificate — we do not self-certify the lot
- Lyophilized, white to off-white powder
- Lot-level traceability with signed COA
Lots that miss the floor on any of the above do not ship.
Every one of those lines refers to a published procedure rather than an in-house convention. The system-suitability parameters that make an area-percent purity figure comparable between laboratories are defined in USP General Chapter ⟨621⟩ Chromatography. What an observed mass can and cannot establish is set out in USP ⟨736⟩ Mass Spectrometry and ⟨1736⟩ Applications of Mass Spectrometry. The characteristics a method has to demonstrate before either number counts as evidence are enumerated in ICH Q2(R2). And "third-party" is a checkable claim: ISO/IEC 17025 accreditation appears in the registries kept by NIST's NVLAP and the ILAC Mutual Recognition Arrangement, not on a laboratory's own marketing page.
What we will not do
We do not discuss human use, dosing, injection protocols, combination with other compounds, or any personal-use scenario. Our products are reference standards for laboratory research. That is the entirety of what we supply.
Analytical questions, lot availability, and method-development conversations are welcome at support@elev8labsrx.com.
Elev8 Labs products are reference standards for laboratory research only. Not for human consumption.