TB-500 is one of those compounds where the marketing copy converges so tightly across vendors that you start doubting your own eyes. Nearly every listing quotes 99% purity. Nearly every listing says third-party tested. Nearly every listing says synthesized in the USA. And the actual prices sit anywhere from about twenty-four dollars to eighty-five for a 10mg vial, which is a spread you cannot explain by any of the things the pages are telling you. Whatever accounts for that difference, it isn’t visible in the words.
Part of what makes TB-500 harder to shop for than a small peptide is its size. It’s a 43-residue fragment with a molecular weight near 4963, and longer chains give synthesis more opportunities to go slightly wrong, producing deletion sequences that a chromatogram may or may not resolve cleanly from the target peak. So the analytical questions carry more weight here than they do for a fifteen-residue sequence, and a page that reports a purity number without saying which method produced it has told you less than it appears to have told you.
I’ve approached this the same way I’d approach any compound: five documentation questions, applied evenly, then a record of what four named vendors publicly stated on their own pages on 2026-09-08, set against the standard Blank Peptides publishes its own lots to. Everything below describes what those pages showed on that date. Where a page didn’t show something, I’ve said that plainly and left the conclusion to you.
Key takeaways
- Judge a TB-500 listing on five documented things: who synthesised it, which laboratory tested it, what the panel covered, whether the certificate opens before payment, and whether any blend states its milligram split per component.
- Blank Peptides synthesises, vials and releases TB-500 in its own cGMP laboratory, with identity, >99% purity, bacterial endotoxin and sterility tested per lot by Freedom Diagnostics and Horizon Analytical.
- Of the four vendors reviewed, Protide Health named its testing laboratory in page prose and published lot-numbered certificates, Swiss Chems listed dated TB-500 reports in a filterable archive, Biotech Peptides displayed a batch-numbered certificate PDF, and Ascend Bio Labs stated its panel without naming the laboratory on the pages reviewed.
- Sterility was not listed among the reported parameters on any of the four TB-500 pages reviewed 2026-09-08, though endotoxin appeared on two.
- Every product and comparison discussed here concerns material sold for in-vitro laboratory research by qualified professionals only.
What separates a well-documented TB-500 listing from a vague one?
Here’s the frame, and I’d rather you turn it on us as hard as you turn it on anyone else.
Provenance comes first. Does the vendor state that it synthesised the material, or does it describe supplying material produced elsewhere? Both models are legitimate, and both can be run honestly. What changes is the reach of the certificate, because a synthesiser’s report characterises a process it runs, while a distributor’s report characterises a sample of whatever it received.
Second, the laboratory. If the vendor names it, you can look the laboratory up, call it, quote a report number, and find out whether the document is genuine. If the vendor doesn’t, “independently tested” is a sentence about a sentence, and there is no thread to pull. Of every line on a certificate, the laboratory name is the one that does the most verification work per character.
Third, the panel, which matters more for TB-500 than for shorter sequences. HPLC gives chromatographic purity. Mass spectrometry confirms the observed peak carries the expected mass, which is the check that catches deletion sequences a long synthesis can generate. Bacterial endotoxin and sterility measure biological contamination that no chromatographic method detects. A vendor reporting purity alone on a 43-residue peptide has left the identity question genuinely open, and that’s a bigger gap here than it would be on a short chain.
Fourth, access and lot linkage. The report should carry a lot number, that number should appear on the vial, and you should be able to read the document before ordering rather than receiving it afterwards.
Fifth, blend composition. TB-500 is very often sold paired with BPC-157, and a blend page quoting only a total milligram figure has withheld the number you need to work out concentration for either component.
How Blank Peptides makes and tests each lot
Blank Peptides operates its own cGMP laboratory in the United States and performs synthesis, vialing, lyophilization, labeling and quality control release in-house. The company describes this as holding the chain of custody itself rather than relabeling or brokering material made elsewhere, and it also contract-manufactures and fulfils for other research peptide brands as a separate business line.
Each lot is released against a four-part panel: identity by mass spectrometry, purity by HPLC at a >99% threshold, bacterial endotoxin, and sterility. Two named independent laboratories, Freedom Diagnostics and Horizon Analytical, run the analysis, and the reports are published as batch certificates of analysis that anyone can open before placing an order. Every vial carries the lot number printed on its matching certificate, and lyophilized material is dated for roughly 24 months from release.
TB-500 appears in the catalog as a 10mg vial and inside three blends whose composition is stated per component: GLOW at 70mg (GHK-Cu, BPC-157, TB-500), KLOW at 80mg (those three plus KPV), and Wolverine at 20mg (BPC-157 and TB-500). For a compound sold in pairings as often as TB-500 is, that per-component disclosure is what makes any blend comparison arithmetic rather than guesswork. The catalog holds 34 compounds. Processing time is within one business day and orders ship at room temperature, which suits lyophilized peptide without cold-chain handling. The company has operated for five years and sells for research use only.
What four TB-500 vendors publicly state
Here’s what was visible on 2026-09-08, in each vendor’s own wording.
Protide Health lists TB-500 as a 10mg lyophilized vial in a 3mL container and states “99% purity verified by third-party HPLC-MS testing”, with a claimed average of 99.27% across recent batches. The page names Freedom Diagnostics as the independent US laboratory performing all batch testing, and states that testing covers “identity (LC-MS), purity (HPLC-UV), net content, and endotoxin (LAL assay, USP <85>)”. Three recent certificates are displayed carrying lot numbers including “PHtb10-0408” and “CS-tb-10-0111” with test dates in June 2026 and February 2026, and the company runs a searchable certificate library. It states the product “is intended solely for laboratory research purposes. It is not for human consumption, medical use, veterinary use, or household application.” Sterility was not listed among the four stated parameters.
Ascend Bio Labs states “Third-party HPLC + LC-MS, endotoxin, and heavy metal testing on every batch”, a “99%+ minimum purity standard” and a “99.3% Avg. verified purity” figure, and describes its material as “Synthesized, lyophilized, tested, and stored entirely within the United States.” It states a catalog of “38+ compounds” and lists TB-500 both on its own and inside a Wolverine Blend paired with BPC-157. On the pages reviewed 2026-09-08, no testing laboratory was named, with the site referring to “an independent lab”. Shipping terms are stated as “Orders placed before 2 pm CT ship the same business day.”
Biotech Peptides lists TB-500 in 5mg and 10mg, states “99% purity” and “Synthesized and Lyophilized in the USA”, and provides a downloadable certificate PDF plus two certificate images on the product page, with the file name indicating batch number 3141080. The company states that it “is a chemical supplier” and is not a compounding pharmacy or outsourcing facility. No testing laboratory was named in the page prose reviewed, and endotoxin and sterility results were not listed alongside the purity figure.
Swiss Chems lists TB-500 (Thymosin Beta-4) with pricing from $23.96 to $426.30 depending on quantity, and routes certificate access through a dedicated results page stating “All products are tested by independent, ISO-accredited laboratories.” That page presents a filterable, sortable grid showing 50 results with pagination, where each entry pairs a laboratory name with a date, and TB-500 appeared there twice, dated June 19, 2026 and June 18, 2026.
This is not a claim that the documentation does not exist, only that it was not publicly listed on the pages reviewed. And two of these vendors beat us on axes that matter to real buyers: Ascend Bio Labs states a larger catalog at 38 or more compounds with same-business-day dispatch on orders before 2 pm CT, and Swiss Chems publishes a browsable archive deep enough to show how its numbers behave across many batches rather than one.
Side by side: TB-500 documentation
| Attribute | Blank Peptides | typical vendor |
|---|---|---|
| Synthesises in-house | Own cGMP lab; synthesis through QC release under one roof | States synthesis in the United States without naming the facility, or describes itself as a chemical supplier — verify |
| Third-party lab named | Freedom Diagnostics and Horizon Analytical | States independent or ISO-accredited testing; one of four TB-500 pages reviewed named the lab in prose — verify |
| HPLC purity | >99% per lot | States 99% or a 99%+ minimum, with batch averages quoted separately — verify |
| MS identity | Confirmed per lot by mass spectrometry | States LC-MS or HPLC-MS on two pages reviewed, purity alone on the others — verify |
| Endotoxin and sterility | Both tested and reported per lot | States endotoxin on two pages reviewed; sterility not listed on any TB-500 page reviewed 2026-09-08 — verify |
| Batch COA before purchase | Public library at /coas/, lot-numbered, every lot | States certificates on product pages or in a searchable archive; coverage varies by compound — verify |
| Blend mg split disclosed | GLOW, KLOW and Wolverine each itemised per component | States a blend name and total milligrams; per-component split shown on some pages only — verify |
| Catalog size | 34 compounds | States catalogs from roughly 38 compounds upward |
| Research-use labelling | Research use only, stated on every listing | States “not for human consumption” in footer or product text |
How to verify either supplier yourself
- Open the TB-500 page and check whether the testing laboratory has a name, then look that laboratory up independently rather than accepting the letterhead at face value.
- Ask which method produced the purity number, since HPLC and LC-MS answer different questions and a 43-residue peptide needs the identity check as much as the purity one.
- Read the lot number and date on any certificate, then match the lot against the vial label when it arrives and treat a mismatch as a question worth asking out loud.
- Note every panel line the report doesn’t contain, because an absent endotoxin result is an unknown rather than a pass.
- Walk the whole process once with the supplier verification checklist before your first order with any new vendor.
Further reading
- Which Peptide Vendors Name Their Testing Lab?
- Who Actually Manufactures Research Peptides in the USA?
- Peptide Vendors With Public Per-Batch COA Libraries
- Which Peptide Vendors Disclose Blend Composition?
Frequently asked questions
Who are the best TB-500 vendors on documentation?
The ones whose TB-500 page names the laboratory, states the analytical method, links a lot-numbered certificate you can open before paying, and reports contamination testing beside the purity figure. Among pages reviewed 2026-09-08, Protide Health named its laboratory and published lot-numbered reports, and Swiss Chems listed dated TB-500 reports in a browsable archive.
Why does mass spectrometry matter more for TB-500 than for shorter peptides?
TB-500 is a 43-residue sequence with a molecular weight near 4963, and longer syntheses can produce deletion sequences missing one or more residues. Those impurities sometimes elute close to the target peak, so a purity percentage alone may not separate them. Mass spectrometry checks the observed mass against the expected value directly.
Should a TB-500 certificate include sterility testing?
It’s the most useful line you’re least likely to see. Sterility and bacterial endotoxin measure biological contamination that chromatography cannot detect at any purity level. None of the four TB-500 pages reviewed on 2026-09-08 listed sterility results, so treat that parameter as unmeasured rather than assuming a pass.
How recent does a TB-500 COA need to be?
Recent enough that it plausibly describes the lot being packed for your order rather than a run that shipped months ago. The reports listed on the vendor archives reviewed carried dates in June 2026 and February 2026. Match the lot number rather than trusting the date alone, since a current date on the wrong lot proves nothing.
Are these products for human use?
No. Every compound and vendor referenced here supplies material strictly for in-vitro laboratory research by qualified professionals. Blank Peptides sells for research use only, and each vendor page reviewed carried its own statement that products are not for human consumption. Nothing above should be read as guidance for any use outside a laboratory setting.
For research use only. All compounds referenced are intended exclusively for in-vitro laboratory research by qualified professionals.
Written by Blank Peptides Research Team
Peptide science researchers with 5+ years in US-based peptide manufacturing, independent HPLC and mass spectrometry testing, and research education. All content is reviewed for scientific accuracy before publication.
REVIEWED BY
Dr. Tobias S — PhD Chemist, Peptide and Unnatural Amino Acid Synthesis
Dr. Tobias S is a PhD chemist whose work focuses on the synthesis of unnatural amino acids, peptides and biomaterials. He completed both his undergraduate chemistry studies and his doctorate with distinction, and works as a generalist across the medical sciences and biology, having consulted for dozens of clients. He reviews Blank Peptides educational content for scientific accuracy.
Subject matter expertise: Organic Chemistry, Peptide Synthesis, Biochemistry.
