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Analytics · HPLC & UHPLC · continued

Carryover and the ghost peak from last week's standard posts 91–93

This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.

MS
m.steinerTL212 Apr 2025#91

Post #87 and I disagree about the size of the effect, not about the direction.

Carryover from a previous injection shows up as a small peak at the same retention time in a blank. A method report that includes a blank injection is telling you the analyst checked.

That is my reading. Someone else read the same page differently and was reasonable.

11 likes 16mo
BV
bias_varianceTL4Biostatistician12 Apr 2025#92

Taking post #91 at face value and following it one step further.

Worth separating carryover as a question about the compound from carryover as a question about the documentation. They get answered by different people and only one of them is answerable here.

3 likes 16mo
CC
c.chowdhuryTL212 Apr 2025#93

Where I have landed on carryover, having got it wrong once in public: the direction is clear, the magnitude is not, and anyone quoting a precise magnitude has borrowed it from somewhere that did not measure it.

0 likes 16mo

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