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c/hplc·submitted 1 year ago by u/priya_ogunleye

integration — 22 things I got wrong before I got it right

Methodbranch of 6 comments

integration — 22 things I got wrong before I got it right. It is the sort of thing everyone half-believes and nobody writes down. Resolution between two peaks depends on retention, selectivity and efficiency. A shallower gradient buys retention and usually resolution, at the cost of peak width and run time. UV…

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6 comments, started 1 year ago
u/priya_ogunleye97 points·1 year ago

area percent is relative to what the detector saw and nothing else

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u/clara_danquah57 points·1 year ago

area percent is relative to what the detector saw and nothing else

This is the whole methodological point of the board in one line.

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u/coa_janitormod · c/coa27 points·1 year ago

Yes — system suitability first. Without it the number is an assertion about the instrument, not the sample.

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u/reverse_image_ron61 points·1 year ago·edited

What wavelength, and what was the gradient?

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u/careful_gradient63 points·1 year ago

Correction: that is a tailing factor, not a plate count. Different diagnostics for different problems.

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u/egfr_watcher16 points·1 year ago

LC-MS for identity, UV for relative quantity

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