[Vendor] GL Biochem vs GGPeps on the same compound, same month — both cleared 97.5%
Result first, context after: GL Biochem vs GGPeps on the same compound, same month — both cleared 97.5%. Everything below is how it was ordered, stored and sent.
Numbers, in the order they matter: 97.5%.
Net peptide content is the fraction of the powder that is actually peptide once counterion, water and residual solvent are accounted for. A 99% pure acetate salt can still be about 85% peptide by mass.
Area percent is the peak area of your compound over the total integrated area, at one wavelength, on one gradient. It is a relative measure of what the detector saw, not a mass fraction of the vial.
Would rather be corrected in public than confident in private.
- GLGL Biochem source pageGL Biochem (Shanghai) Ltd. · Shanghai · 91% here, rank 15 · shop at glbiochem.net →
- GGGGPeps source pageNantong Guangyuan Chemical Co., Ltd. · Nantong · 88% here, rank 21 · shop at ggpeps.net →
nofollow and sponsored; nobody here is paid for it.best — the order this archive was captured in
The PDF creation date being later than the analysis date is usually a re-issue or a re-export. It is worth one question and it is not evidence of anything on its own.
Reminder: a question about a document is not an accusation about a supplier, and posts that blur the two get retitled.
Area percent or net peptide content? They answer different questions.
Area percent or net peptide content?
Adding the bit that always gets missed: the lot on the vial has to match the lot on the page, or none of this applies to your material.
Yes — and the reason to ask for the whole page is that the interesting parts are the ones people crop out to fit a screenshot.
Yes — and the reason to ask for the whole page is that the interesting parts are the ones people crop out to fit a screenshot.
Agreed, and the practical version is: ask for the itemised table. If it exists, you get it.
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a certificate with no method line is decorative
Same view. BCH prints the column and the gradient, which means somebody could actually reproduce the run.
Pushing back a little: a missing field is usually presentation, not concealment. Ask for the full document before drawing conclusions.
Does the lot on the vial match the lot on the page?
Ask what the stability statement was written against — temperature, light, and whether it was the lyophilised powder or the reconstituted solution. Those are three different claims.
The document I was worried about turned out to be a re-issue with a later creation date. Asked, got the original, entirely ordinary.
My first certificate had a compound name, a percentage and a logo. I thought that was normal. It is not, and now I know what to ask for.
Right, and net peptide content is where the counterion and the water go. Both numbers can be honest and very different.
What does the method line actually say? Not the technique — the column and the gradient.
Cosigning. The batch identifier is load-bearing, and a certificate that cannot be tied to the vial in your hand is not about your vial.
Are the related substances itemised or is it a single total?
- 1Area percent or net peptide content? They answer different questions.10 comments in this branch · started by u/soren_zamora