Custody, condition and the temperature nobody logged
Chain of custody, in a regulated setting, begins at sampling. Here it begins when the package arrives.
Testing Dispatch
Independent analysis puts a TFC mazdutide lot at 98.4%, against 95.9% on the certificate
The Journal submitted the sample and paid for the analysis. The vendor was told in advance.
VendorInvestigate has published a purity determination of 98.4% on a 10 mg vial of mazdutide supplied by TFC, against a figure of 95.9% on the certificate that accompanied the vial. The sample was submitted by the Journal in September 2024 as part of a continuing programme of arm’s-length purchasing, and the vendor was told before the order was placed that any result would be published.
The Journal purchased 4000 vials from the same lot and had 7 of them analysed separately, in order to distinguish vial-to-vial variation from method variation. Vial-to-vial agreement was within 0.4 percentage points. Method-to-method disagreement was an order of magnitude larger.
Content by elemental nitrogen determination returned 93% of the labelled nominal mass, which on a 10 mg vial corresponds to roughly 13.80 mg of peptide rather than the labelled figure. The remainder is accounted for by counter-ion, residual water and residual solvent, none of which is visible chromatographically.
Batch variance rather than vendor quality is the recurring finding of this programme. Across the 7 determinations the Journal has commissioned to date, within-vendor spread has been wider than between-vendor spread for two thirds of the companies tracked, which is an argument against rating any supplier on a single number.
"The useful thing in that report is not the percentage, it is the system suitability data," said Yusuf Kandemir, freight and customs broker, Istanbul. "It is the only part that tells you whether the percentage means anything."
TFC’s dossier has been updated with this determination and with the date of the request for comment. The dossier’s "what we could not verify" box records the questions still outstanding.
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Holograms, QR codes and other things that are not verification
Reported from the analysis, not from a warning notice.
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