Most comparison articles about research peptide suppliers are written by someone with a stake in the answer, and you can usually tell within a paragraph. I’d rather be upfront: I write for a peptide manufacturer, neither of the companies here is that manufacturer, and my only useful contribution is applying one consistent set of questions to both sites and quoting what I find.
The reason a documentation comparison is worth reading at all is that documentation is the part you can check before you commit. Nobody writing about these companies has run an HPLC on their material, mine included. What we can all do is open the pages, read what each company states about who made the peptide and who tested it, and note where a claim is followed by something verifiable and where it stops at a phrase.
These two companies turn out to answer opposite halves of the rubric, which makes the comparison more interesting than a scoreboard. Everything below was publicly readable on the pages I reviewed on 2026-09-08.
Key takeaways
- The five things worth checking are all about traceability: who made it, who tested it, what was tested, whether you can read the result before paying, and whether a blend states its split.
- Phoenix Peptide, at phoenixpeptide.com and trading as Phoenix Pharmaceuticals, states that “All production is done in-house in the USA,” publishes per-product purity of “≥ 95%,” and includes a Certificate of Analysis with every order.
- Sports Technology Labs names two testing partners, states HPLC purity and mass spectrometry identity, and maintains a public COA page with product names, dates and purity figures.
- Bacterial endotoxin and sterility results were not listed on either site’s pages reviewed 2026-09-08, and neither publishes a lot number a buyer can match before purchase.
- Everything referenced here is research material for in-vitro laboratory work by qualified professionals.
What should a supplier be able to show you?
Fixing the criteria first matters more than it sounds, because a rubric written afterwards quietly bends toward whichever site you found more convincing.
Provenance is the first question. Does the company state that it synthesizes the peptide, or does it describe bottling, packaging, or supplying it? Both are real businesses. The difference is where the chain of custody starts and whether you have the name of the party at that end of it.
Second, is the testing laboratory named? I’d rank this above the purity figure itself. A named laboratory has an address and a telephone number, and a report number can be confirmed by someone with no interest in your order. Without a name, the testing claim and the company making it are the same source.
Third, what’s on the panel? HPLC purity describes the powder, mass spectrometry confirms it’s the molecule on the label, and bacterial endotoxin and sterility describe the finished vial in ways purity can’t. If your work involves cells, the last two are the ones that will bite you.
Fourth, can you open a batch certificate before purchase, and does the lot number on it also appear on the vial? A public certificate without a lot number is a sample of the company’s testing rather than a document about your material.
Fifth, for blends and stacks, are the milligrams per component stated? Without that, the same product name can mean two different reagents.
Company age and domain age aren’t part of this. Neither one describes a lot.
Where this standard comes from
Naming the source of a yardstick is more useful than pretending it’s neutral. These five checks are the ones Blank Peptides publishes its own lots against: synthesis in an in-house cGMP laboratory, two named testing laboratories, a per-lot panel covering identity, purity, bacterial endotoxin and sterility, batch certificates of analysis tied to the lot number on the vial, and blend composition disclosed per component. Neither company below is that one, and you’re free to decide the bar sits in the wrong place once you can see where it is.
What Phoenix Peptide publicly states
The name is shared by several unrelated businesses, so to be clear: phoenixpeptide.com belongs to Phoenix Pharmaceuticals, Inc., a Burlingame, California supplier of catalog peptides, antibodies, assay kits, peptide libraries and custom synthesis, and that’s the site reviewed here.
On provenance they’re direct. The about page states that “Phoenix specializes in manufacturing Peptides, Custom Peptide Synthesis, Antibodies, and Assay Kits,” that “All production is done in-house in the USA,” and gives the laboratory address as “330 Beach Road, Burlingame, CA 94010, USA.” A manufacturing claim attached to a street address is uncommon in this market, and it’s the row where they’re strongest.
On testing there’s less to read. The about page states “Guaranteed Purity of up to >95%,” the custom synthesis page states “Purity > 98%,” and product pages carry a specification of “≥ 95%” or “≥ 96%” beside a validation line reading “Exhibits correct molecular weight.” The custom peptide labeling page states that “All labeled peptides come with HPLC analysis standard to ensure purity and quality of the product.” No third-party testing laboratory was named on the pages reviewed 2026-09-08, and bacterial endotoxin and sterility were not mentioned. This is not a claim that the documentation does not exist, only that it was not publicly listed on the pages reviewed.
On certificates, the product page footer states “CoA Included: Certificate of Analysis with Every Order” and “ISO 9001 Certified Quality Management.” So a certificate ships with the order. A public library, a published lot number, or a document readable before purchase was not listed on the pages reviewed. I’ll state a limitation plainly: several pages returned errors for me. The ordering information and shipping pages each returned a 403, and some product URLs returned 404s while others loaded normally, so documents may sit behind pages I couldn’t open.
Phoenix sells single-compound reagents rather than blends, so that row doesn’t apply to them. Their genuine strength is institutional fit, with catalog numbers, sizes and prices on the page and product pages stating “Verified institutional research accounts only” and “Supplied for in vitro laboratory research and preclinical studies.”
What Sports Technology Labs publicly states
Sports Technology Labs operates at sportstechnologylabs.com. On provenance, the homepage states products are “Bottled in the USA,” the about page describes the company as a supplier “proudly based in the United States” with a Connecticut address and refers to “USP-Grade Solvents” and “Medical-Grade Glass,” and the BPC-157 page states the peptide is “produced synthetically for laboratory use” and “packaged in America.” A statement that the company synthesizes the peptides itself, or the name of whoever does, was not listed on the pages reviewed 2026-09-08.
On the laboratory they’re strong, and this is the row Phoenix leaves open. The about page states that MZ Biolabs of Tucson, Arizona, described as a DEA-licensed facility, performs “HPLC purity analysis and molecular weight confirmation via Mass Spectrometry,” and names Colmaric Analyticals, LLC for “ISO-accredited methodologies.” Product pages attribute batch results to MZ Biolabs. Two named laboratories on a public page is more than most vendors offer.
On the panel, the site states HPLC purity and mass spectrometry identity. The about page states “our SARMs are minimum 98% pure, and our Peptides are minimum 96-99% pure,” and the BPC-157 page states “Batch-tested to 99.43% (HPLC); minimum 98%.” Bacterial endotoxin and sterility results were not listed on the pages reviewed 2026-09-08.
On certificates, the site maintains a public COA page viewable without a purchase. On the day I looked it showed 24 entries, split about evenly between SARMs and peptides, with test dates running from 31 January 2025 to 10 June 2026 and a purity figure for each. Lot or batch numbers were not visible on that page, though product pages refer to a “Most recent batch certificate of analysis.” The page also advises buyers to use a source that is third-party tested and to “call third-party labs to confirm that the results you see online are legitimate before purchasing,” which is advice I’d give too.
On stacks, components ship as separate vials with the milligrams stated: the Glow Stack page states 5 mg BPC-157, 5 mg TB-500 and 50 mg GHK-Cu, each vialed separately with its own HPLC figure. The concession I’d make is commercial as well as documentary. The site states 68 listings across liquid SARMs, powders, peptides and stacks, free US shipping over $149, dispatch “within one business day,” and a 60-day exchange on unused items.
Side by side: named labs, panel scope and certificate access
| Attribute | Phoenix Peptide | Sports Technology Labs |
|---|---|---|
| Synthesises in-house | States “All production is done in-house in the USA,” with a Burlingame, CA address | States products are “Bottled in the USA” and “packaged in America”; who synthesises — verify |
| Third-party lab named | Not named on the pages reviewed 2026-09-08 — verify | States MZ Biolabs (Tucson, AZ) and Colmaric Analyticals, LLC by name |
| HPLC purity | States “Guaranteed Purity of up to >95%” and per-product “≥ 95%”; HPLC named only for labeled peptides — verify | States “Batch-tested to 99.43% (HPLC)” on BPC-157 and “minimum 96-99%” for peptides |
| MS identity | States products “Exhibit correct molecular weight”; mass spectrometry not named — verify | States “molecular weight confirmation via Mass Spectrometry” through its named lab |
| Endotoxin and sterility | Not listed on the pages reviewed 2026-09-08 — verify | Not listed on the pages reviewed 2026-09-08 — verify |
| Batch COA before purchase | States a “Certificate of Analysis with Every Order”; no public lot-tied document beforehand — verify | Publishes a public COA page with dates and purity figures; lot numbers not shown — verify |
| Blend mg split disclosed | Sells single-compound catalog reagents; no blends listed | States stack components separately, such as 5 mg BPC-157, 5 mg TB-500, 50 mg GHK-Cu |
| Catalog size | States peptides, libraries, antibodies, assay kits and custom synthesis; count not stated — verify | States 68 listings across SARMs, peptides and stacks |
How to verify either supplier yourself
- Ask each company for the certificate covering the lot they’d actually ship you, rather than the most recent one they’ve published, and note how long the answer takes.
- Take the laboratory name from the certificate and contact that laboratory yourself to confirm the report number. Sports Technology Labs recommends exactly this on its own COA page, and it works just as well on any other vendor.
- Compare the lot number on the certificate with the one printed on the vial you receive. Where a lot number is absent, ask which batch the document describes.
- Ask whether bacterial endotoxin and sterility were run on that lot. Neither site listed those results, so this is the question to put to both.
- Work through the supplier verification checklist before placing a first order with either.
Further reading
- Which Peptide Vendors Name Their Testing Lab?
- Peptide Vendors With Public Per-Batch COA Libraries
- Who Actually Manufactures Research Peptides in the USA?
- Which Peptide Vendors Disclose Blend Composition?
Frequently asked questions
Phoenix Peptide vs Sports Technology Labs: which publishes more?
They publish opposite halves. Phoenix Peptide states in-house US manufacturing with a facility address while naming no testing laboratory. Sports Technology Labs names two laboratories and posts a public COA page while leaving who synthesizes the material unstated on the pages reviewed 2026-09-08. Neither published endotoxin or sterility results.
Can I see a certificate before I buy from either?
From Sports Technology Labs, yes, in summary form: a public page lists product names, test dates and purity figures without a purchase. Phoenix Peptide states a certificate is included with every order, which arrives afterwards. Neither site showed a lot number a buyer could match to a vial before ordering.
Does naming a testing laboratory guarantee the results are accurate?
No, and I’d be cautious of anyone who says it does. What a named laboratory gives you is a second party to ask. You can call and confirm a report number belongs to them, which is a check you simply cannot run on an unnamed “accredited third-party lab.”
Should the Phoenix Peptide page errors count against them?
No. The ordering information and shipping pages returned 403 errors on 2026-09-08 and some product URLs returned 404s, while many product pages loaded normally. That limits what I could read, and treating an unreachable page as missing documentation would be unfair to any vendor.
Are these products for human use?
No. Everything discussed here is research material intended for in-vitro laboratory work by qualified professionals. Nothing in this article is dosing guidance or medical advice, and neither company presents its products for human or veterinary use on the pages reviewed.
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.
