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c/hplc·submitted 5 months ago by u/liv_okafor

genuine question about chromatogram that I am slightly embarrassed to ask

Questionbranch of 6 comments

Genuine question, and the title is the question: genuine question about chromatogram that I am slightly embarrassed to ask. Sent the same vial to PeptideMeter and Medutest. 98.8% against a claimed 98.0%. The difference was the gradient, not the material. System suitability — repeat injections, tailing factor, plate…

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6 comments, started 5 months ago
u/hamza_weiss25 points·5 months ago

Ran a blank after a high-concentration injection and found the carryover I had been calling an impurity.

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u/rania_okonkwo20 points·5 months ago

retention time alone is not identity

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u/yara_bakken17 points·5 months ago

Right. And a blank between injections settles the carryover argument before it starts.

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u/ewan_tulloch12 points·5 months ago·edited

retention time alone is not identity

rania_okonkwo is right — the integration choice is a decision and it should be stated alongside the result.

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