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Reference standard · Research use only
Also known as TB-500 Fragment · TB-500 (fragment 17-23) · TB4 Fragment 17-23 · Thymosin β4 (17-23) · Ac-LKKTETQ
Thymosin β4 (TB-500) fragment preparation · actin-binding region
Price, MOQ and lead time come in your written quote — usually within 24 hours. No account needed.
Compound facts
| Name | TB-500 (Fragment 17-23) |
|---|---|
| Also known as | TB-500 Fragment · TB-500 (fragment 17-23) · TB4 Fragment 17-23 · Thymosin β4 (17-23) · Ac-LKKTETQ |
| CAS number | (fragment preparation, no single registered CAS; listed on batch COA) |
| PubChem CID | 62707662 |
| Molecular formula | C38H68N10O14 |
| Molecular weight | 889.02 g/mol |
| Sequence | Ac-LKKTETQ |
| Appearance | White to off-white lyophilized powder |
| Purity specification (HPLC) | ≥ 99.0% |
| On every batch COA | RP-HPLC purity · ESI-MS identity · Bacterial endotoxin · Fill amount (content per vial) |
| On request | LC-MS/MS sequence confirmation · Net peptide content · Water content (Karl Fischer) · Counter-ion content (e.g. acetate, TFA) · Microbial limits |
| Storage | 2–8°C, protect from light |
| Strengths per vial | 2 mg · 5 mg · 10 mg |
| Pack | 10 vials per kit |
| MOQ | On request |
| Lead time | 7–14 days |
| Use | Research use only — not for human or veterinary use |
Identity data from the Lyochem product catalogue, checked against PubChem and registry records. The batch COA of your lot is the record for that lot's results. How to verify a COA
Lot documentation
Values belong to the lot. Ask for the COA of the offered lot before you order.
Independent test fails? Full refund. How it works
Overview
TB-500 Fragment is a fragment preparation derived from the TB-500 / Thymosin β4 sequence rather than the full 43-residue peptide. Interest in fragment forms of Thymosin β4 rests on the actin-binding region of the parent molecule, the part of the sequence that carries the actin-sequestering behaviour studied in cell-migration, angiogenesis, and tissue-repair models; a shorter construct is therefore used in research where the question is which portion of the parent sequence drives an observed effect. It is not a synonym for TB-500: the two are separate catalogue items with different fill codes, and a study that intends the full-length 43-mer should order TB-500 rather than this fragment. Because "TB-500 Fragment" is a preparation name rather than a single registered chemical entity, the exact residue span, molecular formula, and mass are established from the batch-specific Certificate of Analysis rather than from the catalogue label. Ask sales for the COA matched to the offered lot and read the sequence span, purity method, counter-ion, and water content actually recorded there. If the buyer's written procedure requires LC-MS/MS sequence coverage to distinguish the fragment from the parent 43-mer or from a near-mass truncation, define that method, acceptance rule, sample, reporting format, timing, and cost before quotation. Fills of 5 mg and 10 mg match the TB-500 vial formats for side-by-side comparison work.
Applications & buyer fit
Repair peptides — BPC-157, TB-500, PEG-MGF — ship primarily to research laboratories. The applicable batch COA records the tests actually completed. Tandem-MS sequence evidence is an additional agreed scope when the buyer's written procedure requires it, not a blanket requirement to repeat release testing.
Academic Laboratories
Universities, medical schools, and government research institutes qualifying a reference standard for a method-development or in vivo workflow.
Biotech R&D Groups
Preclinical biotech and pharmaceutical discovery teams sourcing characterized peptides for receptor-pharmacology, screening, and method-development campaigns.
Every lot has its own batch-specific CoA — RP-HPLC purity, ESI-MS identity, bacterial endotoxin and fill amount, plus any analytical scope agreed at quote stage — tied to the exact lot you receive.
Review a representative batch CoA before you order, so you can confirm the packet matches what your method or sponsor audit needs.
Supplied strictly as a research reagent to research institutions — not a finished dosage form and not for human administration. Buyer qualification runs at the inquiry stage.
Regulatory note
A fragment preparation of the TB-500 / Thymosin β4 sequence, carried under a preparation name rather than a single registered CAS. The residue span and identity are recorded on the batch-specific COA and should be confirmed there rather than inferred from the catalogue name; state explicitly at order placement whether the full-length TB-500 or this fragment is intended. Supplied for Research Use Only.
Frequently asked questions
The two are different materials with different fill codes, so the distinction has to be read from the paperwork rather than the name. The batch COA states the sequence span actually supplied, and the intact mass reported by ESI-MS separates a fragment from the 43-residue parent by a wide margin, making a mix-up detectable on inspection. Where the buyer's procedure needs residue-level proof — for example to rule out a truncation of the parent that happens to sit near the fragment mass — LC-MS/MS coverage reads the b- and y-ion ladder across the supplied chain; agree that method, acceptance rule, reporting, timing, and cost with sales before quotation rather than assuming it appears on every lot.
Anchor the comparison to documentation rather than to the shared catalogue name. Confirm on the matching COA which residue span was supplied and the purity method and figure, and, where reported, the counter-ion form and Karl Fischer water content, since counter-ion and bound water shift the true peptide mass per vial and therefore the molarity of any reconstituted stock. Record the lot number for both the fragment and the parent in the method file so a later result can be traced to two specific characterized batches, and re-verify identity on each new lot instead of treating lots as interchangeable — for a preparation-name SKU the certificate, not the label, is the identity anchor.
Send any vial from your order to an independent laboratory of your choice. If the report shows the product does not meet the specification on its COA — purity below the stated minimum, or an identity that does not match — share the report with our sales team and we refund that product in full.
TB-500 (Fragment 17-23)
Related peptides
43-mer
Full-length Thymosin β4 (43 residues)
Also in nasal spray
15-mer
Body Protection Compound 15-mer
Also in nasal sprayAlso in capsules
Co-characterized tissue-repair pairing (BPC-157 + TB-500)