purity

Right: MKM cagri — Medutest came back 97.7% against a claimed 97.0%. I paid for this one myself, nobody sent me anything, and the receipts are in the comments. The…

The title is the argument: area percent is the most under-discussed thing on this board. Here is the rest of it. Started keeping a folder of every certificate I have…

how much of what we believe about integration actually comes from LC-MS threads. Searched first, found three threads that contradict each other, hence the post. Chased…

Asking properly rather than in a comment on somebody else’s thread: how do you actually verify test results. On inter-lab disagreement, which generates more heat here…

batch is doing more work than we give it credit for. I have gone back and forth on this for months. The four things a certificate must carry, and what each one is for.…

The claim in the title is exactly the claim I am making: is 99.0% actually fine or am I being sold a rounding error. Nothing implied beyond it. To save the first four…

chromatogram is doing more work than we give it credit for — a position I have arrived at slowly and would like tested. A shoulder that does not baseline-resolve cannot…

the LC-MS rule is doing its job and people should stop complaining — posting the reasoning in public because a policy you cannot inspect is just a preference. The…

related substances are doing more work than we give it credit for, and I am aware this is a minority view on this board. Sent one vial to VendorInvestigate and…

Title says it — 5th independent test on HJ — 99.2% on a claimed 99.0%, and the trend is the interesting part — so here is the boring supporting detail that makes it…

The title is the argument: method development is the most under-discussed thing on this board. Here is the rest of it. Area percent is the integrated area of your peak…

Slightly embarrassed to be asking this, but: why does nobody talk about batch. Spent four months confusing area% and mass% in every post I made here. One explainer…

how much of what we believe about batch actually comes from related substances threads — that is what I am asking, and I have already read the wiki twice. Ask what the…

Genuine question, and the title is the question: how much of what we believe about purity actually comes from related substances threads. Related substances itemised…

The title is the whole question — how much of what we believe about HPLC actually comes from method development threads — but here is why I am asking. KP sent me the…

The title is the argument: we are measuring HPLC at the wrong time and calling it noise. Here is the rest of it. Area percent is the integrated area of your peak over…

Posting this as a discussion rather than a claim: three years of water content threads, summarised so you do not have to read them. Why the same vial can honestly…

related substances — what am I missing here — that is what I am asking, and I have already read the wiki twice. Ask what the stability statement was written against —…

Short version of the title, which is already short: split one vial across Janoshik and Medutest — 98.7% and 98.3%. Longer version underneath. Since the title puts…

genuine question about area percent that I am slightly embarrassed to ask. I am not trying to be the "source?" guy. I would just like a source. The four things a…

the chromatogram advice in here is 2 years out of date — a position I have arrived at slowly and would like tested. Numbers, in the order they matter: 2 years.…

Question in the title, detail here: can we stop arguing about related substances until somebody posts a number. Started keeping a folder of every certificate I have…

The claim in the title is exactly the claim I am making: SSA BPC — Medutest came back 98.1% against a claimed 97.5%. Nothing implied beyond it. To save the first four…

Posting this because the title is the whole finding — GGPeps vs GL Biochem on the same compound, same month — both cleared 99.0% — and a number without its method is a…

The title is the whole question — how much of what we believe about purity actually comes from batch threads — but here is why I am asking. The template is vendor,…