Vol. 3, No. 6 — June 2026Independent since 2024

TheCompound Journal

Reporting on incretins, compounding & the peptide supply chain

A monthly journal of record.
30 issues · 32 contributors
Not medical advice. We sell nothing.

Provenance

Who signed this, and what did they undertake by signing it

Two signatures — one who performed the work, one who approved its release — are the ordinary regulated convention and are almost unknown here.

Two quite different documents circulate under the heading certificate of analysis, and conflating them is the commonest category error in this market. A manufacturer’s certificate is a self-declaration: the company that made the material states what it found. A third-party report is a measurement performed by an independent laboratory on a submitted sample, and it says nothing whatever about any other vial in the lot. The first covers the batch and is only as good as the manufacturer’s systems. The second is independent and covers a sample. Buyers routinely treat each as though it had the other’s virtues.

A certificate is a document, not a test

The confusion at the root of almost every dispute about certificates is a category error. A certificate of analysis is not a measurement. It is a record asserting that measurements were made, by named methods, on identified material, on a stated date, with stated outcomes, and that somebody reviewed and released the batch on that basis. The measurements exist elsewhere: in instrument data files, in analyst notebooks, in a laboratory information system. The certificate is the summary that travels with the goods.

This distinction has a practical consequence. When the Journal wants to know whether a purity figure is sound, we do not scrutinise the certificate; we ask for the underlying laboratory report and, where possible, the chromatogram. The certificate can only tell us what somebody concluded. The chromatogram tells us what the instrument saw, and the two are separated by decisions about integration, thresholds and reporting that the certificate does not record.

It follows that a certificate’s value is almost entirely a function of whether it can be traced back to that underlying evidence. A document with a batch number, a date, a named method and a named analyst is checkable in principle even if nobody ever checks it. A document with a percentage and a logo is not checkable by anyone, including the company that issued it, and the difference between those two situations is invisible to a buyer who reads only the number.

The header block: identifying the object

The top of a certificate answers the question, what is this document about. A complete header names the product, gives a catalogue or item number, gives the batch or lot number, states the quantity or fill weight, names the manufacturer and the site, and identifies the customer or order where applicable. Some add a chemical name, a sequence in single-letter code, a molecular formula and a molecular weight, all of which are useful because they let a reader check the theoretical values used elsewhere on the page.

The sequence in particular is worth insisting on. A certificate that prints the one-letter sequence has given a reader the means to calculate the expected mass independently, and therefore to check the identity line. Two of the twenty companies in the Journal’s dossier programme do this as standard. It costs nothing and it converts one line of the document from an assertion into a verifiable claim.

What a header should never do is identify the product only by a trade name. A vial described as a proprietary blend with no chemical identity, no formula and no sequence cannot be checked against anything, and a certificate for such a product is a document about a name. This is a documentary observation rather than an accusation, and the remedy is trivial: print the sequence.

The analytical work behind these products is often better than the paperwork that reports it.

On why a bad document is not a bad product

The footer: dates, signatures and the release statement

The bottom of a certificate carries the dates, the signatures and any boilerplate. A complete footer gives the date of manufacture, the date of analysis, and either a retest date or an expiry date with the convention named. It gives the name and role of the person who performed or compiled the testing, and separately of the person who reviewed and approved it. It states the storage conditions under which the stated properties hold. And it states, in a research-chemical context, the research-use-only restriction.

The two-signature convention is worth explaining because its absence is so universal here that its purpose is forgotten. Separating performance from approval is a control against a single person’s error or judgement determining a release. It is cheap, it requires no equipment, and it is the ordinary practice in every regulated laboratory. Its function is not ceremonial: it means that when a document turns out to be wrong, there is a record of who reviewed it and on what basis.

What the footer should not carry is a signature rendered as a reused image with no accompanying name. That is not evidence of anything improper on its own — scanned signature blocks are common in legitimate commerce — but it removes the one piece of information the block exists to supply, which is the identity of a person who can be asked.

Documentary discrepancies in 63 certificates audited by the Journal
FindingCertificatesResolved on enquiryUnresolved
Batch number absent from the vial itself19145
No specification column for one or more tests17116
Method stated only as an acronym1697
Date of manufacture absent13103
No name in the signature block1174
Expiry date with no supporting stability data963
Molecular weight inconsistent with printed sequence330
Chromatogram identical to one on another document211
Sixty-three certificates supplied to the Journal between the first quarter of 2025 and the second quarter of 2026, covering the twenty companies in the dossier programme and eleven others. “Resolved on enquiry” means the company supplied an explanation or corrected document that the standards desk accepted. No finding in this table is presented as evidence of misconduct by any company.

Signatures, and what an unsigned certificate is

An unsigned certificate is a statement with no author. It may be entirely accurate; it is simply not attributable, and attribution is most of what a release document does. The regulated convention of two signatures — one for the analyst who performed or compiled the work, one for the reviewer who approved its release — exists because release is a decision and decisions benefit from a second reader.

What the Journal looks for is narrower than a wet-ink signature, which nobody expects in a scanned document. We look for a name and a role. “Analysed by: L. Wen, Analytical Chemist. Approved by: Q. Zhang, QC Manager” is worth more than any flourish, because it identifies people who can be asked a question. A certificate signed with an illegible mark and no printed name has supplied the ceremony and withheld the content.

Of the twenty companies in the dossier programme, eleven print a name in the signature block, four print a role without a name, and five print neither. Two of the eleven print two names in the regulated pattern. These are documentary counts and nothing more; a company with no name on the certificate may have impeccable internal records, and several of them, when asked, produced signed internal release records promptly. The point is that a buyer cannot see any of that from the page.

Accreditation, and the scope nobody checks

An accreditation logo on a letterhead means a body has assessed a laboratory against the international standard for testing competence and granted accreditation for a defined scope of methods. The scope is the part that matters and it is published: accreditation bodies maintain public registers listing, for each accredited laboratory, the tests and techniques covered. A laboratory can be validly accredited and the specific test on your certificate can lie outside its schedule.

Checking this takes a few minutes. Find the accreditation number on the document, look it up on the relevant national body’s register, and read the scope. What you are looking for is whether the technique used for your test — reversed-phase HPLC purity, mass spectrometric identity, water determination — appears. Where it does, the accreditation is doing work. Where it does not, the logo is a true statement about the laboratory and says nothing about the test in front of you.

The standard itself is clear that reports must identify what was and was not covered, and that accredited status attaches to activities rather than to organisations as a whole.1 The Journal makes this check on any certificate it intends to cite, and reports the result. It is the single most under-performed piece of due diligence in this market, principally because almost nobody knows the registers exist.

109856137132024 audit2026 audit7143060120180365days between manufacture and analysiscumulative % of certificates
Figure. Cumulative share of audited certificates whose date of analysis falls within a given number of days of manufacture, comparing the Journal’s 2024 audit with the 2026 cycle. Documents missing either date are excluded from both series.

Two documents, one heading

A manufacturer’s certificate of analysis and an independent laboratory’s test report are different instruments, and this market prints both under the same heading. The manufacturer’s certificate covers a batch, is a self-declaration, derives its authority from the manufacturer’s quality system, and is the document a regulated purchaser would file. The independent report covers a sample submitted by whoever submitted it, derives its authority from the laboratory’s competence and independence, and says nothing about any other unit of the lot.

Each has a virtue the other lacks. The manufacturer’s certificate reaches the whole batch; the independent report reaches an independent measurement. Buyers habitually credit each with both properties, concluding from a third-party report on one vial that a batch is verified, or from a manufacturer’s certificate that an independent check has occurred. Neither inference holds.

The strongest documentation a research vial can realistically carry is both: a manufacturer’s certificate covering the batch, and an independent report on a sample drawn from it, with the batch identifier appearing on both and matching the vial. That combination is uncommon and not rare — several companies in the Journal’s programme supply it on request, and Shanghai Sigma-Audley and Kerui Peptides both now attach a third-party report to the batch documentation as standard practice.

The systematic absences, and what each would cost

Peptide content is absent from almost every research certificate, and it is the absence with the largest practical consequence, because it is the number that determines how much peptide a nominal mass represents. Determination by elemental nitrogen analysis or quantitative amino-acid analysis is routine chemistry, and the compendial approach to amino-acid analysis for biotechnological articles is long established.2

Water content is absent nearly as often and is cheap to determine. Counter-ion identity and content are almost universally absent. Residual solvent appears occasionally. Bacterial endotoxin is absent, and its determination requires a different laboratory discipline and different reagents. Sterility is absent, requires fourteen days of incubation, and cannot be compressed. Container closure integrity is absent and is a packaging test rather than a chemical one.

The pattern is consistent: the tests that appear are the ones a chemical supplier’s laboratory already performs, and the ones that do not are the ones that would require a different laboratory. This is a rational commercial arrangement and it becomes a problem only when the resulting document is read as a general assurance of quality rather than as a chemical identity and purity statement, which is what it is and all it claims to be.

A specification is a commitment made before the test. A result reported without one is a commitment made afterwards.

How this publication handles certificates

Four rules, arrived at over two years and revised twice. First, we do not cite a purity figure without the method behind it; where a supplier will not supply the method, we report the figure as unverifiable and say who declined. Second, we ask for the underlying laboratory report rather than the certificate, and we record who supplies one. Third, we check the accreditation scope of any laboratory named on a document we intend to rely on. Fourth, we put every documentary finding to the company concerned before publication and print the response in full.

The fourth rule is the one that has changed our coverage most. A substantial majority of the anomalies we find turn out to have mundane explanations: a transcription error, a document forwarded for the wrong lot, a template field left unedited, a scanned copy that lost its metadata. Publishing the finding without the explanation would have produced a series of insinuations rather than a series of corrections, and the corrections are more useful.

The rules also mean we publish less than we could. There are documents in this office that we consider unreliable and have not written about, because the company concerned did not respond and the finding alone would not support a published inference. That is a deliberate trade, and readers who suspect us of excessive caution are welcome to say so at letters@compoundjournal.com, where several already have.

A necessary distinction between a bad document and a bad product

Almost nothing in this article supports an inference about the contents of a vial. A certificate missing a specification column, an unsigned footer, a stale date of analysis and a batch number that appears only on the carton is a poor document. The material it accompanies may be excellent, and in the Journal’s experience frequently is: the analytical work behind these products is often better than the paperwork that reports it, because the paperwork is produced by a commercial function and the analysis by a laboratory.

The reverse also holds. A beautifully constructed certificate with four columns, two signatures and a named method is evidence of a functioning documentary process and is not evidence about the vial either, since a document cannot testify to material it does not accompany. This is why the Journal reports documents as documents and material as material, and declines to convert one into a claim about the other.

We labour the point because the alternative is a genre of coverage that treats documentary weakness as proof of dishonesty, and that genre is both unfair and useless. Unfair because most documentary weakness in this trade is inherited convention rather than intent. Useless because it gives a reader nothing to do. Reading the document properly gives a reader something to do, which is the entire purpose of this piece.

Readers who take one habit from this piece should take the first minute of the ten-minute check. Find the batch number on the vial. Everything else on the document is a claim about a defined quantity of material, and if the vial is not identifiably part of that quantity then the rest of the page is a well-drafted statement about something else.

References

  1. International Organization for Standardization. ISO/IEC 17025:2017 — General requirements for the competence of testing and calibration laboratories. Geneva, 2017. Clause 7.8 on the reporting of results.
  2. United States Pharmacopeia. General chapter ⟨1057⟩, Biotechnology-Derived Articles — Amino Acid Analysis. USP–NF.
  3. European Directorate for the Quality of Medicines. European Pharmacopoeia, General Notices, on the status of specifications and the demonstration of compliance. Strasbourg.
  4. European Directorate for the Quality of Medicines. European Pharmacopoeia, general chapter 2.5.12, “Water: semi-micro determination.” Strasbourg.
  5. International Council for Harmonisation. Q6B: Specifications — Test Procedures and Acceptance Criteria for Biotechnological/Biological Products. 1999.

Letters to the Editor

5 printed

Selected from correspondence received on this article. Writers are identified by initial, surname and city, verified before printing. Replies are from the desk that filed the piece or from the standards editor. Write to letters@compoundjournal.com.

The composite test table you print as a model is unrealistic. No research supplier is going to run headspace GC and ion chromatography on every lot at these price points, and publishing an aspirational document as a benchmark just makes real certificates look worse than they are.

R. Ekwueme, Awka

The Journal replies

The table note says explicitly that no supplier in our programme issues a document containing every row, and it is offered as a reference rather than as a demand. But you have a point about framing, and we have moved the caveat from the note into the caption.

Nine years buying research chemicals and I had never once looked at the date of manufacture. I checked eleven certificates in my drawer this evening. Four do not carry one.

A. Kirkbride, Leeds

A technical query on your identity row: you specify 4111.1 Da monoisotopic with a tolerance of ±10 ppm, which is 0.04 daltons. Is that not tighter than most contract laboratories will commit to on a peptide of that size?

C. Bąkowski, Łódź

The Journal replies

It is achievable on an orbital trap with internal calibration and is tight for a quadrupole time-of-flight on external calibration. The row is drawn from a real certificate issued by a laboratory running the former. We should have said so, and the note now does.

You put every documentary finding to the company before publication, which is admirable and also means you are letting companies that do not reply escape coverage entirely. Silence should have a cost.

D. Sakamoto, Kobe

The Journal replies

It does, and we should make it more visible. Non-response is recorded in the dossier register and published there. What we will not do is publish an inference we cannot support merely because nobody objected to it, and that constraint does protect the unresponsive. We accept the trade knowingly.

You describe reused chromatogram images as a tell. I work in a contract laboratory and I would note that some data systems export a representative overlay rather than the individual injection, so identical-looking traces can occur legitimately across a batch series. It is still worth asking about; it is not the smoking gun your article implies.

M. Bogdanović, Podgorica

The Journal replies

A useful qualification and the text has been softened. The observation remains worth making; the inference we drew from it was stronger than the practice supports.

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