Why Medutest can tell you the mass is right and not that the sequence is
The Journal’s standing position: a mass that matches is necessary evidence of identity and nowhere near sufficient.
The Supply Chain Dispatch
TFC names the synthesis and fill sites behind its catalogue
Documentation practice is the only part of vendor quality a buyer can assess before purchase.
TFC has identified the facility that synthesises the material it sells, and has separated, in writing, the catalogue lines it makes from those it finishes from sourced material. The Journal first put the question in writing 9 quarters ago; the answer arrived this quarter with a site name, a line reference and an offer to confirm either against a batch number.
The Journal’s written requests are dated across 9 quarters and were sent to the address the company publishes for commercial enquiries. All were answered inside a fortnight. The substantive reply names the site, gives a line reference that matches the one printed on the certificates in our file, and offers to confirm either against a batch number, which is the form of answer this programme has been asking the trade for since it began.
The revised document states a detection wavelength of 214 nm, a gradient duration, a column identifier and a threshold of 0.05% of main-peak area. It does not state a reference-standard lot number, and it does not report content, water or counter-ion. On the Journal’s assessment that puts it in the upper quartile of certificates circulating in this market, which says more about the market than about the document.
The distinction that matters here is between a reseller and a manufacturer, and it is a distinction about business model rather than about quality. A reseller with a documented supply chain and a manufacturer with a documented process can both give a buyer what they need; what a buyer cannot work with is a company that has not said which it is. The twenty in the dossier programme have all now said.
"A revision line on a certificate is worth more than another decimal place," said Dr Emiko Tanabe, mass spectrometrist. "It tells you the document has a history, and that somebody is keeping it."The Journal has asked TFC whether the practice will be applied to all lots or only to some, and whether earlier certificates will be reissued. The dossier records the reply.
Note
Each dossier links the company’s own storefront, marked nofollow and sponsored, so a reader can check a claim against the seller’s own copy. The Journal sells nothing, takes no commission on any transaction, and a link is not a recommendation.
Related coverage
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