What the paperwork is for, and who it was designed to protect

Certificates exist because a manufacturer selling a material to a purchaser who cannot test it needs a way to transfer information about quality along with the goods, and because somebody eventually needs to be able to reconstruct, months later, what was known about a particular batch at the moment it was released. The second purpose is the one that shapes the document, and it is the one the research-chemical version of the form has almost entirely lost.

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 test table: four columns, and most certificates carry two

The body of a certificate is a table, and a complete one has four columns: the test performed, the method used, the specification applied, and the result obtained. Four columns, one row per test. That structure is not a convention peculiar to pharmaceuticals; it is what a record of controlled testing looks like in any field, because each column answers a question the other three cannot.

The method column is where the detail belongs — not the word HPLC but a method identifier, a gradient, a wavelength, a column chemistry. The specification column states what the batch had to achieve. The result column states what it did. A certificate carrying only test and result has dropped the two columns that make the result interpretable, and this is by far the commonest structural deficiency the Journal encounters.

The compendial framework for validating an analytical procedure exists precisely to establish that a stated method can discriminate what it claims to discriminate, which is why a method reference is not bureaucratic ornament but the hook on which everything else hangs.¹² A named method can be looked up, compared, criticised and repeated. An unnamed one cannot be, and a result generated by one is a number whose provenance stops at the page.

The lines nobody reads: appearance and solubility

Near the top of most test tables sit two entries that buyers skip and chemists do not: appearance and solubility. Appearance is reported as something like “white to off-white lyophilised powder”, and it is a real test with real discriminating power. A peptide cake that is yellow, or grey, or that has collapsed into a glassy plug rather than a light lyophilised mass, is telling you something about the drying cycle, about oxidation, or about a temperature excursion in transit.

Solubility is similarly underrated. A specification reading “clear, colourless solution on reconstitution in water at 1 mg/mL” establishes that the material dissolves at the concentration a user will need, without haze, and haze on reconstitution is a genuine finding: it can indicate aggregation, incomplete removal of a protecting group, or particulate contamination. It is also the only test on most certificates that a buyer can repeat at home.

The reason to press on these lines is that they are cheap, they are already on the form, and they degrade in a way the purity figure does not capture. A certificate reporting a white powder for material that arrives faintly yellow has not been falsified. It has been overtaken by events, which is exactly what a certificate with an eleven-month-old date of analysis should be expected to be.

Water, counter-ion and the mass in the vial

A lyophilised peptide is not pure peptide even when it is chromatographically pure. It is a salt, usually of trifluoroacetic or acetic acid, containing residual water that a hygroscopic powder acquires readily, and sometimes residual solvent from purification. Three lines on a certificate address this and they are usually absent: water content, counter-ion identity and content, and residual solvent.

Water is determined by Karl Fischer titration or by loss on drying, and the pharmacopoeial methods for it are old, settled and inexpensive.³ A peptide containing eight per cent water by mass contains eight per cent less peptide than its label implies, and the figure is not stable: it depends on how the vial was stoppered and how long it has been open. Counter-ion content is a larger contribution still for basic peptides purified in trifluoroacetic acid, where the counter-ion fraction can reach ten to twenty per cent of total mass.⁴

Put these together and the practical statement is the one this department repeats: the nominal mass on a research vial is an upper bound on the peptide it contains, not a value. A certificate that reports purity and is silent on water and counter-ion has told you the material is clean and nothing at all about how much of it there is.

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.

What “conforms” conceals

A statement of conformity is a judgement, not a measurement, and the judgement depends on how the reporting party handles results that sit near a limit. If a specification requires not less than 98.0% and a measurement returns 97.9% with a method uncertainty of ±0.4%, does the batch conform? The answer depends entirely on a policy — whether the limit is applied to the measured value, or to the measured value adjusted for uncertainty, and in which direction. Metrological reporting practice has a settled answer here, which is that a result quoted without its uncertainty cannot be compared to a limit at all.⁵

The accreditation standard for testing laboratories requires that where a statement of conformity is given, the decision rule employed is documented and the report identifies it.⁶ This is not a technicality. Without a decision rule, “conforms” means whatever the person writing it decided it meant on the day, and two laboratories applying different rules to the same measurement will report different verdicts without either being wrong.

In this market decision rules are essentially unknown, and the practical consequence is that the word carries no information about marginal cases. The Journal therefore reports numbers rather than verdicts wherever a number is available, and where a source supplies only a conformance statement we say so explicitly rather than paraphrasing it as a pass. Readers occasionally find this pedantic. It is the difference between reporting a measurement and repeating an opinion.

The template economy

Every organisation issuing certificates works from a template, and the template is a good thing: it enforces completeness, it fixes the layout so that readers know where to look, and it prevents an analyst in a hurry from omitting the method. Internal blank forms with editable fields are ordinary laboratory infrastructure and their existence implies nothing.

What creates the difficulty in this market is a documentary supply chain in which certificates are forwarded, re-exported, retyped and reassembled several times between the laboratory that generated the data and the buyer who reads it. At each step a document can be reconstructed rather than reproduced — the numbers transcribed into a new layout carrying a new logo — and each reconstruction loses the metadata and the internal consistency that would let a reader tell an original from a copy.

The result is a population of documents in which reused layouts, reused chromatogram images and reused dates occur for several different reasons: honest transcription, lazy transcription, forwarding of a document about a different lot, and, at the far end, fabrication. Those causes have very different implications and are hard to distinguish from the page alone. This is why the Journal’s method here is to report the documentary observation and put it to the company, rather than to infer a cause, and why we do not publish a document as fabricated unless the named laboratory tells us it did not issue it.

The ten-minute check

Minute one: find the batch number on the certificate and find it on the vial. Not the carton. If they do not match, or the vial has no number, stop and ask the supplier what the relationship is. Minutes two and three: find the date of manufacture and the date of analysis, and compute the interval. Then compute the interval between the date of analysis and today.

Minutes four and five: read the test table and count the columns. If the specification column is missing, the results cannot be assessed. If the method column is missing or says only HPLC, the purity figure cannot be compared with anybody else’s. Minute six: check the identity line for a theoretical mass, and check whether the convention — monoisotopic or average — is stated. Minute seven: read the signature block for a name and a role.

Minutes eight to ten: list what is not there. Content, water, counter-ion, residual solvent, endotoxin, sterility. Then decide whether any of those matter for what you are doing, which is a question only the reader can answer. The exercise does not establish that a certificate is right or wrong. It establishes whether the document can be checked at all, and in the Journal’s experience roughly a third of certificates in general circulation fail before minute five. Readers who work through this and find something they cannot interpret are welcome to write to standards@compoundjournal.com.

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.