Somewhere on most DSIP product pages there’s a link that says certificate of analysis, and clicking it feels like doing your homework. Then the document opens and you realise you can’t tell much from it. There’s a percentage, usually a chromatogram, and often no laboratory name, no batch identifier that ties to anything you’ll receive, and no indication of whether this report describes material synthesized last month or three years ago. The reassurance the link provides and the information it provides are two different quantities.
Delta sleep-inducing peptide gives you something useful to work with, though. It’s a nonapeptide with a fixed sequence, Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu, CAS 62568-57-4, formula C35H48N10O15 and a molar mass near 848.8 g/mol. Those numbers are published on most listings, which means a certificate reporting a mass gives you an arithmetic check you can run in your head before any money changes hands. Very few buyers run it, and it’s one of the fastest ways to catch a document that doesn’t match the product.
This piece covers what a DSIP certificate needs to contain, then what four named vendors publish about certificate access on their own pages as reviewed 2026-09-08. Everything I say about those vendors is a description of what appeared on the pages, and I’ll keep a firm line between a document that wasn’t linked and a document that doesn’t exist, because I can only speak to the first.
Key takeaways
- A DSIP certificate becomes useful when it names the issuing laboratory, carries a batch number and a test date, states the analyte, and reports identity alongside purity.
- Blank Peptides publishes a dated certificate for every DSIP lot at its public /coas/ library, with identity, >99% purity, bacterial endotoxin and sterility from Freedom Diagnostics and Horizon Analytical.
- PSPeptides links HPLC, heavy metals, endotoxin and sterility reports from its DSIP page, while Core Peptides and Biotech Peptides link a certificate and Swiss Chems routes to a site-wide archive.
- On the pages reviewed 2026-09-08, no vendor in this group named the laboratory that issued its DSIP certificate, and identity confirmation appeared on only one of the four.
- Everything described is laboratory research material sold for in-vitro use by qualified professionals.
What has to be on a DSIP certificate for it to be worth reading?
Read the top of the document before the number in the middle. The number is what you were sold on. The header is what tells you whether the number describes your vial.
The analyte line comes first. It should say DSIP or delta sleep-inducing peptide and, ideally, restate the sequence or formula. If the listing is a sleep-themed blend or a prepared spray, the certificate should account for each component individually, because a purity result on a mixture doesn’t separate into per-component information by itself.
The laboratory comes second, and this is where most certificates in this category fall short. A name and a report number make the document confirmable by anyone willing to send an email. Wording like “tested by an accredited third-party laboratory” with no name attached leaves you unable to check anything, so the certificate ends up resting on the same vendor assurance it was meant to replace.
Third, the batch identifier and test date. Synthesis runs vary, so a certificate describes one run rather than a product line. A report with no batch number, or one that’s clearly older than the material in stock, is history rather than evidence about what you’ll receive.
Fourth, the method list. HPLC purity gives you the share eluting as the main peak. Mass spectrometry establishes which molecule that peak is. Bacterial endotoxin and sterility address contamination that chromatography is blind to, and heavy metals and residual solvents fill in further. A certificate reporting purity alone covers a fraction of the ground it appears to cover.
Fifth, retention. Does the vendor keep prior certificates online alongside the current one? Being able to see three consecutive batches tells you far more about consistency than any single result can, and it’s rare enough that noticing it is worthwhile.
Those five apply to us as much as to anyone, so the next section states what we release against before describing anyone else.
How Blank Peptides makes and tests each lot
Blank Peptides runs a cGMP laboratory of its own in the United States and handles synthesis, vialing, lyophilization, labeling and quality-control release internally. The company describes this as owning the full chain of custody rather than relabeling or brokering material made elsewhere, and it separately contract-manufactures and fulfils for other research peptide brands.
Lot release covers four results: identity by mass spectrometry, purity by HPLC against a >99% threshold, bacterial endotoxin, and sterility. Two named independent laboratories carry out the analysis, Freedom Diagnostics and Horizon Analytical. Reports are published among the batch certificates of analysis, a library grouped by compound with individually dated batches listed underneath, so a DSIP certificate can be opened before ordering rather than requested afterwards. One published DSIP batch record from May 2026 shows 99.36% HPLC purity with endotoxin, identity and appearance recorded as passing, tested by Horizon Analytical. Vials are printed with the lot number matching their report, and lyophilized material is dated at roughly 24 months from release.
DSIP is stocked as a 10mg lyophilized vial in a 34-compound catalog. Blends there have composition itemised 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). Processing runs within one business day, shipments go at room temperature with no cold-chain handling, and lyophilized peptide is well suited to that. The company has traded for five years and sells for research use only.
What four named DSIP vendors publicly state about certificates
PSPeptides gave the fullest certificate access of the four on 2026-09-08. Its DSIP listing, a 5mg vial at $39.99, states “99%+ purity (third-party HPLC and mass spectrometry verified)” and states that each order ships “with a batch-specific Certificate of Analysis (COA) documenting purity verification via reverse-phase HPLC and identity confirmation via mass spectrometry.” Four documents were linked from the page: the 5mg lot certificate, heavy metals, endotoxin and sterility, dated June 2026, and the page states the certificates are “batch-specific, not lot-averaged”. Publishing sterility and heavy metals reports alongside HPLC is more than most vendors in this category do, and it deserves saying plainly. The performing laboratory is described only as independent and third-party, without a name.
Core Peptides lists DSIP at 5mg for $41.00 under SKU P-DSIP-5, states “>99%” purity and describes the contents as lyophilized powder, with volume tiers at five and nine units. A certificate-of-analysis link was present on the product page and openable before purchase. No sequence, CAS number or laboratory name appeared in the page copy reviewed.
Biotech Peptides lists DSIP at 5mg for $44.00, states “99% purity”, and offers a certificate download from the product page reachable without an account. The site states it “is a chemical supplier” rather than a compounding pharmacy and limits sales to “research professionals of 21+ years of age”. The issuing laboratory was not named on the page reviewed.
Swiss Chems sells DSIP at 2mg from $24.95 and publishes the sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu, CAS 62568-57-4, formula C35H48N10O15 and molar mass 848.82 g/mol, with “99% Purity Guaranteed” and the statement “Every batch is independently lab tested for identity, purity and potency.” Rather than linking a certificate for the lot in stock, the page pointed to a site-wide lab-testing area which states “All products are tested by independent, ISO-accredited laboratories” and hosts downloadable HPLC reports dated through mid-2026. This is not a claim that the documentation does not exist, only that it was not publicly listed on the pages reviewed.
Side by side: DSIP certificate access
| Attribute | Blank Peptides | Typical DSIP vendor |
|---|---|---|
| Synthesises in-house | Own cGMP lab; synthesis through QC release in-house | States US synthesis or sourcing without naming who performed it — verify |
| Third-party lab named | Freedom Diagnostics and Horizon Analytical | States “independent”, “third-party” or “ISO-accredited”; no name on the DSIP pages reviewed 2026-09-08 — verify |
| HPLC purity | >99% per lot, with a published batch result of 99.36% | States “99%”, “>99%” or “99%+” — verify |
| MS identity | Confirmed per lot | States mass spectrometry identity on one of four vendors reviewed 2026-09-08 — verify |
| Endotoxin and sterility | Both tested per lot | States both on one of four reviewed; not listed on the other three — verify |
| Batch COA before purchase | Public library at /coas/, grouped by compound and dated batch | States a linked certificate on three of four; one directs to a site-wide archive — verify |
| Certificate tied to a batch number | Lot printed on the vial and on the report | States “batch-specific, not lot-averaged” on one of four; batch linkage not shown on the others — verify |
| Prior certificates retained | Dated batch history published per compound | States a retained earlier certificate on one of four reviewed 2026-09-08 — verify |
| Research-use labelling | Research use only, stated site-wide | States “not for human or animal consumption” or equivalent site-wide |
How to verify either supplier yourself
- Open the DSIP certificate before ordering and read the analyte line, batch number and test date first, treating the purity percentage as the last thing you check rather than the first.
- Compare any observed mass on the report against roughly 848.8 g/mol for C35H48N10O15, since a match turns purity into identity and a mismatch is a reason to stop.
- Email the laboratory named on the certificate with the report number and ask for confirmation, which takes a couple of minutes and is simply unavailable when no lab is named.
- Save the certificate at the point of order, then compare its batch number to the vial label when the package arrives, and ask for the matching report if they differ.
- Work through the supplier verification checklist before placing a first order with any supplier.
Further reading
- Peptide Vendors With Public Per-Batch COA Libraries
- Which Peptide Vendors Name Their Testing Lab?
- Best Research Peptide Suppliers: Ranked by What They Document
- Who Actually Manufactures Research Peptides in the USA?
Frequently asked questions
What should a DSIP COA show before I buy?
The analyte name, the issuing laboratory, a batch number, a test date and the methods run. HPLC purity and mass spectrometry identity together answer the two central questions, while bacterial endotoxin and sterility cover contamination that chromatography cannot detect. Anything absent from that list is a result you would need to commission independently.
Where do vendors put the DSIP certificate?
Three patterns appeared on the pages reviewed 2026-09-08: a certificate linked directly from the product page, a set of separate reports for purity, metals, endotoxin and sterility linked together, and a site-wide testing archive reached from the listing. A library organised by compound and dated batch is what lets you check the specific lot you’ll be shipped.
How do I confirm a DSIP mass result?
Use the published formula C35H48N10O15 and its molar mass of about 848.8 g/mol, then compare against the observed mass on the certificate. Adducts and salt forms produce small predictable offsets. A large discrepancy indicates the document and the product description are describing different material, which is worth resolving before ordering.
Does an older certificate on the page still tell me anything?
Yes, provided you read it as history rather than as a description of current stock. Seeing two or three consecutive batches lets you judge whether results hold steady across runs. What it cannot do is stand in for a certificate covering the lot you’ll actually receive, so ask for that one separately.
Are these products for human use?
No. Every product referenced here is sold strictly for in-vitro laboratory research by qualified professionals. Blank Peptides sells for research use only, and the vendors described publish their own restrictions, including “not for human or animal consumption” and “Laboratory/In-Vitro Experimental Use Only”. Nothing above describes or implies 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.
