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c/hplc·submitted 9 months ago by u/week_four_wall

[Question] LC-MS — what am I missing here

Questionbranch of 7 comments

LC-MS — what am I missing here — that is what I am asking, and I have already read the wiki twice. Bought a second-hand instrument and learned more in six months of fixing it than in three years of reading traces. QYB sent me the column, the gradient and the theoretical mass without being asked. That is a short list…

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7 comments, started 9 months ago
u/ewan_marchand2 points·9 months ago

This. A shoulder that does not baseline-resolve is a question, not a quantity.

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u/quiet_reader_991 point·9 months ago·edited

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

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u/zeynep_zielinski1 point·9 months ago

Push back: a longer run is not automatically better resolution. You are trading peak width for time and the ratio is what matters.

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u/week_four_wallOP1 point·9 months ago·edited

Is that baseline drawn by the software or by hand?

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u/week_four_wallOP1 point·9 months ago

What wavelength, and what was the gradient?

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u/yara_boateng1 point·9 months ago

report the method or do not report the number

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u/hugo_bergstrom1 point·9 months ago

system suitability before you believe any number on the run

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