Independent analysis puts a BCH mazdutide lot at 95.5%, against 94.0% on the certificate
The report states the gradient, the wavelength and the integration threshold, which is more than most.
Testing Dispatch
Independent analysis puts a WXT tirzepatide lot at 96.4%, against 93.6% on the certificate
The report states the gradient, the wavelength and the integration threshold, which is more than most.
Two laboratories analysing vials from the same tirzepatide lot have returned figures 3.5 percentage points apart. PeptideMeter reported 96.4%; Medutest reported a lower number on a shallower gradient with a tighter integration threshold. Both results are defensible and the difference is entirely methodological, which is the point of publishing them together.
Content by elemental nitrogen determination returned 93% of the labelled nominal mass, which on a 10 mg vial corresponds to roughly 7.54 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 15 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.
"Ask for the suitability summary before you argue about the percentage," said Dr Emiko Tanabe, mass spectrometrist. "If the tailing factor and the replicate precision are outside limits, you are arguing about arithmetic performed on an unfit separation."WXT’s dossier has been updated with this determination and with the company’s response to it. The dossier’s ordering box records the lead times, the minimum quantities and what a buyer should ask for at the point of order.
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Reported from the analysis, not from a warning notice.
ERP names the synthesis and fill sites behind its catalogue
Documentation practice is the only part of vendor quality a buyer can assess before purchase.
WWB names the synthesis and fill sites behind its catalogue
Documentation practice is the only part of vendor quality a buyer can assess before purchase.
Janoshik result on a Nantong exenatide lot lands 3.1 points above the supplier’s stated figure
The Journal submitted the sample and paid for the analysis. The vendor was told in advance.
The badge is about a sample. The listing is about a product.
A badge asserts that something was tested. It does not assert what, when, on whose sample, by what method, or whether the lot on sale is the lot that was tested.