VendorInvestigate result on a Guangzhou retatrutide lot lands 3.9 points below the supplier’s figure
The result is unremarkable. What the report omits is not.
TheCompound Journal
Reporting on incretins, compounding & the peptide supply chain
Analytics
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.
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.
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.
Check the vial, not the box. The batch number is the only thing connecting the page to the material.
The standing rule in this departmentAn 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.
| Interval | Certificates | Share |
|---|---|---|
| Within 14 days | 31 | 49% |
| 15–60 days | 12 | 19% |
| 61–180 days | 5 | 8% |
| Over 180 days | 2 | 3% |
| One or both dates absent | 13 | 21% |
| Where only one date was present the certificate is counted in the final row. The median interval among the fifty documents carrying both dates was eleven days, which is unremarkable and reassuring; the more consequential interval — between the date of analysis and the date the buyer receives the vial — is not recorded on any certificate the Journal has seen. | ||
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.
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.
The next piece in this department turns from the document to the institutions that generate it: the four independent testing services this market relies on, what each measures, and the awkward fact that in most cases the party paying for the test is the party being tested. Two of the four advertise in this publication, which is disclosed on our funding page and is stated again wherever the coverage touches them.
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.
I supply research peptides and I want to push back on the specification column point. We sell from a catalogue of six hundred products. Writing a meaningful individual specification for each would take a year of somebody’s time, and a generic one would be exactly the decorative limit your article criticises. What would you actually have us do?
— K. Rautio, Tampere
A fair challenge. Our answer is that a generic limit stated honestly is better than no limit at all, provided the typical result is also published so a reader can see the margin. What we object to is a decorative limit presented as a control. Publishing your process capability alongside it removes the objection entirely, and costs you a spreadsheet.
The most useful sentence in the piece is the one saying a bad document is not a bad product. I have spent two years on forums watching people conclude the opposite from a missing signature block, and it has made the whole conversation about honesty rather than about paperwork.
— M. Ferrari, Trieste
That inversion is the reason we wrote the final section, and we would rather be accused of excessive caution than contribute to it.
The result is unremarkable. What the report omits is not.
The sequence predicts the failure mode. A methionine predicts oxidation; an asparagine followed by a glycine predicts deamidation; a cysteine predicts disulphide scrambling.
A unit is a volume. A dose is a mass. The bridge between them is concentration, and concentration is a number somebody has to calculate.
The report states the gradient, the wavelength and the integration threshold, which is more than most.
The result is unremarkable. What the report omits is not.
At low concentrations a measurable fraction of peptide can adsorb to glass and plastic surfaces, and the loss is largest exactly where it is least expected.