A supplier suspends shipping to Spain after 6 consecutive customs detentions
The route did not close because of a rule about peptides.
Testing Dispatch
Janoshik result on a Xianning semaglutide lot lands 4.3 points above the supplier’s stated figure
The supplier confirmed the determination and supplied the method behind its own figure inside a week.
Two laboratories analysing vials from the same semaglutide lot have returned figures 4.3 percentage points apart. Janoshik reported 98.9%; PeptideMeter 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.
Reported figures across the set were: highest 98.9%, lowest 97.0%, median close to the midpoint of the two. Every report in the set stated a detection wavelength, and 16 of them stated an integration threshold. The Journal has asked the laboratory to publish thresholds on all reports as a matter of routine.
Reported figures across the set were: highest 98.9%, lowest 97.0%, median close to the midpoint of the two. Every report in the set stated a detection wavelength, and 16 of them stated an integration threshold. The Journal has asked the laboratory to publish thresholds on all reports as a matter of routine.
Purity became this trade’s single figure of merit because it is the cheapest measurement to obtain and the easiest to compare. Peptide content, which determines how much drug is actually in a vial, costs several times as much and is quoted as a priced addition by most of the twenty companies in the Journal’s dossier programme rather than carried as a standard release test. Sterility and endotoxin are separate disciplines again, and are neither tested nor claimed.
"The figure is not wrong and neither is theirs," said Marek Doležal, analytical chemist and former QC laboratory manager. "They are answers to two different questions and the trade has decided to pretend there is only one question. Print the gradient and the argument disappears."
QST’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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