COA

12th independent test on QST — 98.6% on a claimed 98.5%, and the trend is the interesting part. One vial, one service, one member paying, which is the only kind of…

the area percent question that gets asked weekly, answered properly. It is the sort of thing everyone half-believes and nobody writes down. Asked FGP for the…

Something I keep coming back to: the certificate of analysis advice in here is 3 years out of date. Since the title puts numbers in the shop window: 3 years. How to ask…

why does nobody talk about area percent — that is what I am asking, and I have already read the wiki twice. Water content 3.8%, acetate 6.2%, purity 99%, net peptide…

Trying to work out what makes a document a result rather than a general statement about a product line. The one in front of me — FGP cagrilintide — has a compound name,…

Posting this because the title is the whole finding — what does "related substances 1.4%" actually mean for my vial — and a number without its method is a rumour. 1.4%.…

area% is not mass% and here is exactly why it matters. Two minutes of reading now saves an argument later. Related substances itemised individually is a much stronger…

Asking properly rather than in a comment on somebody else’s thread: help me understand purity, I have read the wiki twice. LC-MS gives you identity; UV purity gives you…

Short answer, for anyone who finds this from a search: no. Longer version. A COA from an actual laboratory is exported from instrument software or from a LIMS. The PDF…

10th independent test on ERP — 97.2% on a claimed 97.0%, and the trend is the interesting part. That is the headline. The document, the batch and the service are below…

Housekeeping: proposal — a flair for related substances posts. Water content 3.8%, acetate 6.2%, purity 99%, net peptide about 90% of label weight. All four numbers…

The title is the argument: reading related substances threads from 2024 and half of it aged badly. Here is the rest of it. Started keeping a folder of every certificate…

help me understand water content, I have read the wiki twice. Searched first, found three threads that contradict each other, hence the post. Asked QSC for the…

Slightly embarrassed to be asking this, but: how do i tell an HPLC-UV COA from an LC-MS one at a glance. My first certificate had a compound name, a percentage and a…

reading water content threads from 2024 and half of it aged badly. It is the sort of thing everyone half-believes and nobody writes down. Net peptide content is the…

we are measuring purity at the wrong time and calling it noise. Change my mind, genuinely — I have no stake in being right about this. How to ask for a batch record…

the purity rule is doing its job and people should stop complaining. Disagreement welcome, but bring a concrete alternative wording. UV at 214nm sees the peptide bond…

related substances are the most under-discussed thing on this board. Change my mind, genuinely — I have no stake in being right about this. Water content 3.8%, acetate…

Question in the title, detail here: does anyone get a COA from their compounding pharmacy. Paid noticeably more at one clinic than another for what turned out to be the…

Posting this as a discussion rather than a claim: the fake COA question that gets asked weekly, answered properly. Why this board insists on dates and documents rather…

Ran these on the same day, same method, same column, injections back to back. One is GL Biochem raw material, one is a reseller vial of nominally the same compound and…

split one vial across Janoshik and Medutest — 95.1% and 97.6%. I will put the method line and the batch identifier up front because that is what makes this checkable.…

how do you actually verify fake COA. I am not trying to be the "source?" guy. I would just like a source. Asked a new shop for a batch-specific certificate before…

reading batch threads from 2024 and half of it aged badly. Making the case below, and I expect to lose some of it in the comments. My first certificate had a compound…