Most of the time this comparison is easy in a depressing way, because one site names a laboratory and the other says “third-party tested” and you are done in four minutes. That is not what happens here. Both of these companies name the laboratory doing their analysis, both quote methods rather than adjectives, and both put an accreditation reference in writing. The separation has to come from somewhere else, and it turns out to come from what you can read before you hand anyone a card number.
I write for a peptide manufacturer, and neither company below is that manufacturer, so nothing here shifts depending on which one you pick. Five questions, put to both sites in the same words, with answers quoted from their own pages and every unanswered row logged as a gap in what was published rather than as a claim about what happens off-page.
The observations come from sportstechnologylabs.com and certified-pep.com as they stood on 2026-09-08. One of the two sites moved behind a login partway through the review, and I have said exactly where that happened rather than guessing at what sat on the other side.
Key takeaways
- What separates two suppliers is who synthesized the lot, which laboratory tested it, how wide the panel ran, whether a certificate opens before payment and matches a lot number, and whether blends print per-component milligrams.
- Sports Technology Labs publicly names MZ Biolabs in Tucson, Arizona and Colmaric Analyticals, LLC, and keeps a certificate index readable without an account.
- Certified-PEP publicly names “Vanguard Laboratory, located in Olympia, Washington” as ISO/IEC 17025:2017 accredited and states a panel covering “endotoxin, heavy metals, purity, and sterility tests.”
- On the pass reviewed 2026-09-08, the Certified-PEP certificate library required an account login, and lot numbers were not visible on the Sports Technology Labs certificate index.
- Everything referenced here is research material for in-vitro laboratory work by qualified professionals, and none of it is guidance for use in people or animals.
What actually separates two peptide vendors?
I set the rubric before either name appears, since a standard assembled after reading the sites is a standard shaped by whichever homepage read better.
Provenance is first. Does the company state that it synthesizes the compound, or does it describe manufacturing happening somewhere it does not name, or supplying material it did not make? Read the verbs literally. Several arrangements exist in this market and more than one of them carries good material. What changes is who holds the synthesis records the day a result comes back strange.
Second, is the laboratory named? This sits above the purity figure in my ordering. A laboratory with a name and a city can be looked up, its accreditation scope can be read, and it can be asked whether a report number belongs to it. An accreditation standard quoted with no name attached gets you halfway and stops.
Third, how wide is the panel? HPLC purity reports what fraction of the material is a single species and nothing beyond that. Mass spectrometry confirms the species is the sequence on the label. Bacterial endotoxin and sterility describe the finished vial rather than the powder, which matters for anything cell-based, and USP chapter references behind those two claims tell you which procedure was followed rather than leaving the word “sterile” floating on its own.
Fourth, access and linkage. Can you open a batch certificate before paying, and does its lot number also appear on the vial that arrives? Those two conditions together turn a document into evidence about your material. Either one on its own is weaker than it looks, because a certificate you cannot read yet and a certificate that matches nothing both leave you trusting a summary.
Fifth, blend disclosure. A blend sold by total milligrams with no per-component split cannot be written into a methods section, so the split is what separates a citable product from a decorative one. Company age and domain age stay out of this list, since neither describes a lot.
Where this standard comes from
These five checks are the ones Blank Peptides publishes its own lots against, as batch certificates of analysis posted per lot. Neither company in this comparison is that one. Naming the source of a yardstick before applying it to two other businesses seems fair, because a measurement means something only if the party holding the ruler would accept being measured by it.
What Sports Technology Labs and Certified-Pep publicly state
Sports Technology Labs sells at sportstechnologylabs.com and ships its own inventory. On provenance, the homepage states products are “Bottled in the USA,” and the about page describes a supplier “proudly based in the United States” at a stated Shelton, Connecticut address, referring to “USP-Grade Solvents” and “Medical-Grade Glass.” The BPC-157 page states the peptide is “produced synthetically for laboratory use” and “packaged in America.” A statement that the company performs synthesis itself, or naming the party that does, was not listed on the pages reviewed 2026-09-08.
On testing, the about page states MZ Biolabs in 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.” Purity is stated as “our SARMs are minimum 98% pure, and our Peptides are minimum 96-99% pure,” with the BPC-157 page stating “Batch-tested to 99.43% (HPLC); minimum 98%.” Its concession is access, and it is a real one: the certificate page lists product names, test dates and purity figures with no account and no purchase, running from January 2025 to June 2026 across roughly 18 peptide entries and 12 SARM entries. Lot numbers were not visible on that index, though product pages refer to a “Most recent batch certificate of analysis.” Bacterial endotoxin and sterility results were not listed on the pages reviewed 2026-09-08. Stacks ship as separate vials with amounts stated, the Glow Stack listing 5 mg BPC-157, 5 mg TB-500 and 50 mg GHK-Cu, and terms are stated as 68 listings, free US shipping over $149 and dispatch “within one business day.”
Certified-PEP sells at certified-pep.com and describes itself as “a chemical supplier,” stating it is “not a compounding pharmacy” under FDA regulations 503A or 503B. On provenance, the homepage states products are “Manufactured in a cGMP facility in Texas,” with the operator of that facility not named on the pages reviewed 2026-09-08. The site answers where and what kind without answering who.
Its testing disclosure is the strongest single element in this comparison, and that is the concession. The lab testing page names “Vanguard Laboratory, located in Olympia, Washington,” described as “ISO/IEC 17025:2017” accredited and “accredited through the Department of Ecology and the Department of Health for the analysis of Drugs and Controlled Substances.” The homepage states “Purity standards of 99% or higher with US Labs.” The stated panel covers “endotoxin, heavy metals, purity, and sterility tests” including “USP <61> (Microbial Enumeration Tests) and USP <71> (Sterility Tests),” and the company states it uses HPLC and “mass spectrometry to confirm identity and purity.” The about page states “Every batch includes third-party results you can read and verify” and describes “Cold-chain storage (-20 °C lab-grade freezers).” All four assays named, a laboratory you can look up, and USP chapters behind the sterility claim is more than most companies in this market attempt.
The catch sits on access. The certificate library returned a notice on the pass reviewed: “Due to regulatory changes in this industry, we now require an account login to access product information and continue browsing.” No certificates were visible without an account, so I could not confirm whether they carry lot numbers, whether Vanguard’s name appears on the documents themselves, or how far back the archive runs. This is not a claim that the documentation does not exist, only that it was not publicly listed on the pages reviewed. The shop showed roughly 24 peptide listings across pagination, blends among them, with the per-component milligram split visible on some listings and absent on others. Shipping is stated as FedEx 2-Day Air for orders before 3PM EST, and products are stated to be “sold for research, laboratory, or analytical purposes only, and are not for human consumption.”
Side by side: two named laboratories, two kinds of access
| Attribute | Sports Technology Labs | Certified-Pep |
|---|---|---|
| Synthesises in-house | States products are “Bottled in the USA” and “packaged in America”; who synthesises not stated — verify | States “Manufactured in a cGMP facility in Texas”; facility operator not named — verify |
| Third-party lab named | States MZ Biolabs (Tucson, AZ) and Colmaric Analyticals, LLC, with batch results attributed to MZ Biolabs — verify | States “Vanguard Laboratory, located in Olympia, Washington”, ISO/IEC 17025:2017 accredited — verify |
| HPLC purity | States peptides are “minimum 96-99% pure” and a batch figure of “99.43% (HPLC)” — verify | States HPLC testing and “Purity standards of 99% or higher” — verify |
| MS identity | States “molecular weight confirmation via Mass Spectrometry” at MZ Biolabs — verify | States “mass spectrometry to confirm identity and purity” — verify |
| Endotoxin and sterility | Not listed on pages reviewed 2026-09-08 — verify | States endotoxin plus USP <61> and USP <71> sterility testing — verify |
| Batch COA before purchase | States a public COA page with test dates and purity figures, readable without an account; lot numbers not visible — verify | States a certificate library; access required an account login on the pass reviewed — verify |
| Blend mg split disclosed | States per-vial amounts for separate-vial stacks, such as 5 mg, 5 mg and 50 mg for Glow — verify | States blends; per-component split shown on some listings and absent on others — verify |
| Catalog size | States 68 listings across liquid SARMs, SARM powders, peptides and stacks — verify | Roughly 24 peptide listings across paginated pages — verify |
| Research-use labelling | States products are “for research purposes only and are not for human consumption” — verify | States products are “sold for research, laboratory, or analytical purposes only” — verify |
The trade is visible in two rows. Certified-PEP states the wider panel and puts USP chapters behind it, then asks you to make an account before reading anything. Sports Technology Labs states a narrower panel and lets you read the index straight away, with the lot number missing from what it shows you.
How to verify either supplier yourself
- Call the named laboratory rather than the vendor. Both companies give you one, so ask MZ Biolabs or Vanguard Laboratory whether the report number you were shown belongs to them, and whether peptide analysis sits inside their accreditation scope.
- Where a library is behind a login, ask support to send the certificate for the lot they would ship you this week before you create an account, and see whether the document carries a lot number and the laboratory’s name.
- Read the method lines rather than the headline percentage, and check whether endotoxin and sterility ran on your lot or on an earlier qualification batch.
- On blends, ask for the milligram split in writing where the listing does not print it, because a total-milligram figure alone cannot support a working concentration.
- Grade both against the supplier verification checklist so the same rows get answered for each.
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?
- Best Research Peptide Suppliers: Ranked by What They Document
Frequently asked questions
Sports Technology Labs vs Certified-Pep: which documents more?
Certified-PEP states the wider panel, naming Vanguard Laboratory with an ISO/IEC 17025:2017 reference and listing endotoxin, heavy metals, purity and sterility with USP chapter numbers. Sports Technology Labs states fewer assays and gives better access, publishing a certificate index with dates and purity figures that opens without an account.
Do both companies name their testing laboratory?
Yes, which is uncommon in this market. Sports Technology Labs states MZ Biolabs in Tucson, Arizona and Colmaric Analyticals, LLC. Certified-PEP states Vanguard Laboratory in Olympia, Washington. Both names can be checked independently, and asking either laboratory to confirm a report number is a reasonable step before ordering.
Which one lets you read a certificate before buying?
Sports Technology Labs published an index of product names, test dates and purity figures with no login on the pages reviewed 2026-09-08. The Certified-PEP certificate library returned a notice requiring an account to continue browsing on that same pass, so its documents were not readable without registering.
Does either state where its peptides are made?
Certified-PEP states products are “Manufactured in a cGMP facility in Texas” without naming the operator. Sports Technology Labs states products are “Bottled in the USA” and “packaged in America” without stating who performs the synthesis. Both leave the provenance row partly open on the pages reviewed 2026-09-08.
Are these products for human use?
No. Everything referenced here is research material intended for in-vitro laboratory work by qualified professionals. Purity percentages, laboratory names and certificate libraries describe documentation and nothing else. Nothing in this article is dosing guidance, medical advice, or a recommendation to use any compound outside a controlled 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.
