someone explain HPLC to me like I have not read a paper in years
Trying to get a straight answer on this: someone explain HPLC to me like I have not read a paper in years. The system suitability argument, since it comes up whenever somebody posts a number without one. Before the sample result means anything, the instrument has to be shown to be fit that day: replicate injections…
Do you have the mass, or only the UV trace?
Do you have the mass, or only the UV trace?
rania_okonkwo is right — the integration choice is a decision and it should be stated alongside the result.
What did system suitability look like on that sequence?
Can you post the trace with the axes labelled?
Is that baseline drawn by the software or by hand?
a shoulder is not an impurity until you can resolve it
Not convinced by that integration. Dropping the baseline there absorbs part of the shoulder into the main peak.
This. A shoulder that does not baseline-resolve is a question, not a quantity.
Retention time shifted 0.4 minutes and I assumed the worst. It was the column temperature.
a shoulder is not an impurity until you can resolve it
This is the whole methodological point of the board in one line.
This is the whole methodological point of the board in one line.
Agreed. And the corollary is that the method line on a certificate is not decoration, it is the number’s provenance.
Ran a blank after a high-concentration injection and found the carryover I had been calling an impurity.