Representative packaging image · verify the ordered lot
Decision summary
Key benefits
Defensible research value includes actin-sequestration and cell-migration assays, angiogenesis and wound-model experiments, comparison with the isolated 17–23 fragment, analytical identification and anti-doping method development
Claims of systemic tissue repair, athletic recovery or clinical wound benefit for a research lot are not established and must remain hypotheses or published-programme background.
Published research context is presented for literature orientation only. It is not a dosing, treatment or human-use instruction.
Qualification data
Specifications to confirm against the released lot
CAS
77591-33-4
Formula
C212H350N56O78S
Molecular weight
4963.51 g/mol
Appearance
Lot-specific lyophilized research peptide; confirm colour and physical form on the released-lot COA
Purity
Lot-specific chromatographic purity plus quantitative peptide content; confirm N-terminal acetylation, counterion, water and deletion-related peptides separately · target, verify batch COA
Storage
Follow the released-lot label, COA and lot-specific stability data. Do not assume 2–8°C storage, a 28-day reconstituted period or finished-formulation instructions without supporting data for the supplied salt form, matrix and container.
Identity, purity and content are separate release questions.
Identity
Confirm the stated molecule and supplied form. Start with the matching batch COA; request sequence-level evidence only when the buyer's written procedure requires it and availability or a separate scope has been agreed.
Purity
Review RP-HPLC method conditions, wavelength, integration and related-peak handling. A percentage without the method is not enough.
Content
Net peptide content is not the same as gross lyophilized powder weight. Ask which assay supports the stated amount and whether water/counter-ion is addressed.
Stability
Follow the storage condition stated on the batch COA or label from receipt onward.
Research context
What researchers study about TB-500 (Thymosin Beta-4, full-length)
This catalogue record defines TB-500 as full-length thymosin-β4: the mature 43-residue, N-terminally acetylated sequence Ac-SDKPDMAEIEKFDKSKLKKTETQEKNPLPSKETIEQEKQAGES-OH. Thymosin-β4 is an abundant G-actin-sequestering peptide; its central LKKTETQ motif (residues 17–23) is the actin-binding region studied in cell-migration, angiogenesis and wound-model research. The seven-residue Ac-LKKTETQ fragment is a different molecule with a different mass and CAS and has its own record. Commercial naming is inconsistent, so sequence and mass—not the name alone—must control identity. Clinical programmes such as RGN-259 used defined full-length formulations; their results do not transfer to research lots or establish any human use. The 2026 WADA Prohibited List names thymosin-β4 and its derivatives, including TB-500, under S2.3.
Appropriate laboratory contexts include full-length identity and N-acetylation, actin-sequestration assays, comparisons with the 17–23 fragment, cell migration, angiogenesis and repair models, proteolytic stability, formulation and analytical anti-doping research
No approved clinical indication applies to a research lot.
Mechanism context
The question the literature is testing
Thymosin-β4 binds monomeric G-actin and buffers the unpolymerised actin pool; the LKKTETQ region (residues 17–23) carries the principal actin-binding activity. Published work also links the full-length peptide to cell migration, angiogenic signalling and inflammatory modulation, but effects depend on model, concentration and formulation. Experimental interpretation requires authenticated material, defined concentration and matrix, and appropriate fragment or vehicle controls.
Dose / exposure contextProtocol-specific; verify the cited primary source
Routes and exposure contexts summarize cited studies or approved finished-product labels. They are not instructions for administering this RUO material; no customer dose is provided.
Evidence boundaries
Compatibility, limitations and decision context
Not for human or veterinary administration
Safety findings from defined full-length thymosin-β4 clinical formulations cannot establish the safety of a research lot
Identity confusion with the 17–23 fragment, incorrect content, impurities, aggregation, contamination and unvalidated endotoxin or sterility are material risks
The 2026 WADA Prohibited List names thymosin-β4 and its derivatives, including TB-500, under S2.3.
Interactions reported in the literature
No human combination or compatibility guidance applies
Wolverine Blend, BPC-157, CJC-1295, IGF-1, ipamorelin, GHRP-6 and melanotan-II synergy claims were removed because vendor or community co-use does not establish pharmacological interaction, efficacy or safety
Laboratory mixtures require single-component controls and component-resolved analysis.
Literature context is not a supplier release result or human-use instruction. Follow your institution's approved laboratory risk assessment.
Batch documentation
TB-500 (Thymosin Beta-4, full-length) batch COAs
Laboratory: Manufacturer's QC laboratoryTests: HPLC purity · MS identity · endotoxin · fill amount
2 mg
5 mg
10 mg
Previews are blurred on purpose so the documents cannot be reused; third-party reports show their first page only. Sales sends the clear full version for the product and strength you ask about.
Published COAs show recent representative batches and may not be the newest. For a quote or shipment, sales confirms the lot and sends its COA.
Third-party reports, added progressively
Previews of the first page of third-party reports are on our Quality page and on the matching product pages; sales sends the full report on request. You can also send any vial from your order to an independent laboratory of your choice. Unless agreed otherwise in writing, the buyer pays for optional testing.
Help reviewing your COA
Need help reading a batch COA or third-party report? Sales can explain the test items, specifications and how the results relate to the lot under discussion.
On every batch COA: HPLC purity · MS identity · endotoxin · fill amount · Verify LyoPep
Third-party reports for TB-500 (Thymosin Beta-4, full-length)
Reports from Qorix (tjqxgd.com), a third-party analytical laboratory in Tianjin, China: HPLC purity and MS identity of the sample tested.
Laboratory: Third-party laboratoryTests: HPLC purity · MS identity
10 mg
Previews are blurred on purpose so the documents cannot be reused; third-party reports show their first page only. Sales sends the clear full version for the product and strength you ask about.
Ask for the current packet, not a generic certificate
Require the 43-residue sequence assignment and N-acetylation confirmation, intact mass, peptide mapping or tandem-MS coverage able to resolve positional deletion variants, chromatographic purity, quantitative peptide content, counterion, water, residual solvents, related peptides, container integrity and lot-specific stability
A clear reconstituted solution or a generic COA does not prove identity, content, sterility or stability.
Batch COA for the released lotHPLC purity with method contextMS identity resultEndotoxin resultFill amount (measured content per vial)SDS and handling statement
Available fills
Quote the fill and pack configuration you need
Reference SKUFillBase pack
BT22 mg10 vials
BT55 mg10 vials
BT1010 mg10 vials
Other format
Also available as a nasal spray (US stock)
10 mL nasal spray bottle
Besides lyophilized vials, TB-500 (Thymosin Beta-4, full-length) is also supplied as a nasal spray solution, shipped from our US stock.
Strengths
2 mg · 5 mg · 10 mg
Bottle sizes
10 mL or 20 mL
Minimum order
10 bottles per strength and bottle size
Ships from
Our US stock
Handling
Plan storage before the parcel arrives
Follow the released-lot label, COA and lot-specific stability data. Do not assume 2–8°C storage, a 28-day reconstituted period or finished-formulation instructions without supporting data for the supplied salt form, matrix and container.
State the destination and timing so receipt can be planned, then move the material into its stated storage condition on arrival.
Buyer FAQ
Terms to settle before the purchase order
Can a buyer arrange third-party testing?+
Yes. You can send any vial from your order to an independent laboratory of your choice. If you want the laboratory, specification, sampling, method and acceptance rule agreed with us before testing, sales confirms them in writing. Unless otherwise agreed in writing, the buyer pays the cost of this optional testing.
What if my own lab test shows the product is out of specification?+
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.
Does HPLC purity prove peptide content?+
No. Chromatographic purity describes the relative peak profile under a stated method. Identity, water, counter-ion, residual solvents and assay/content may require separate methods.
How should material be stored after delivery?+
Move it into the storage condition stated on the batch COA or label as soon as it arrives, and record the package condition on receipt.
How are payment terms handled?+
Available methods and milestones depend on order value, destination and project type. The pro forma invoice should state currency, bank details, fees, payment milestones and the release condition.
Why must the testing laboratory understand peptide chemistry?+
Free-base and salt forms, hydrophilic and hydrophobic sequences, aggregation and adsorption can change sample preparation and method suitability. Use a laboratory experienced with the molecule class.
These are buyer-qualification references, not claims that this RUO material is regulated, certified or released under those frameworks. Applicability depends on the buyer's workflow and jurisdiction.
Selected sources
Literature behind the research context
Identity: full-length thymosin-β4 comprises 43 residues, PMCID PMC319967; CAS 77591-33-4; PubChem CID 16132341. Actin binding: Philp et al., FASEB J 2003, the actin-binding site on thymosin-β4. Clinical background: RGN-259 literature, PMCID PMC6043477, concerns defined full-length formulations. Fragment boundary: Esposito et al., Drug Test Anal 2012, and Ho et al., Journal of Chromatography A 2012, PMID 23084823, concern the N-acetylated 17–23 fragment, not this record. Anti-doping context: official 2026 WADA Prohibited List, S2.3.
01
Synthesis and characterization of the N-terminal acetylated 17-23 fragment of thymosin beta 4 identified in TB-500, a product suspected to possess doping potential
Drug Testing and Analysis · 2012 · peer-reviewed original research (analytical/forensic chemistry)
0.1% RGN-259 (Thymosin β4) Ophthalmic Solution Promotes Healing and Improves Comfort in Neurotrophic Keratopathy Patients in a Randomized, Placebo-Controlled, Double-Masked Phase III Clinical Trial
International Journal of Molecular Sciences · 2022 · peer-reviewed original research (Phase III randomized controlled clinical trial, published as journal article)
Questions buyers ask about TB-500 (Thymosin Beta-4, full-length)
Is this TB-500 record full-length thymosin-β4 or the 17–23 fragment?+
Full-length. This catalogue identity is the mature 43-residue thymosin-β4 sequence with N-terminal acetylation, the material the listed fills contain. The seven-residue Ac-LKKTETQ fragment corresponding to residues 17–23 is a separate molecule with different mass, CAS identity and evidence, and has its own record (TB-500, fragment 17–23). The product name alone is ambiguous in commercial channels, so sequence, intact mass and released-lot form must control procurement.
Can RGN-259 dry-eye or corneal-healing trials support this material?+
Only as background. RGN-259 and related programmes used full-length thymosin-β4, so they concern the same parent molecule, but in defined finished formulations and protocols. A research lot is not that formulation: its identity, content, impurity profile, sterility and stability need their own evidence, and the trial results do not establish any use outside an approved protocol.
What evidence should confirm a full-length thymosin-β4 lot?+
Request the 43-residue sequence assignment with N-terminal acetylation, intact mass consistent with the acetylated full-length chain, peptide mapping or tandem-MS coverage able to separate positional deletion variants, chromatographic purity, quantitative peptide content, counterion, water, residual solvents, related peptides, container integrity and lot-specific stability. Endotoxin, bioburden and sterility are separate study-dependent attributes.
