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

[Discussion] chromatogram is doing more work than we give it credit for

Discussionbranch of 14 comments

Genuinely asking, not being difficult. Everyone in c/glp1uk repeats that method development is important. I believe it, but I have never seen anyone show why, and when I search I get 3 threads of people agreeing with each other. Is there a paper? Is there a measurement? Or is this one of those things that is true…

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14 comments, started 1 year ago
u/nabila_espinoza-38 points·1 year ago

Gradient goblin mode: changed the solvent composition 14 times, finally got good resolution on a gradient peak.

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u/micro_bump_mick1 point·1 year ago

What was the column and what gradient?

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u/hplc_hobbyistruns their own column1 point·1 year ago

Disagree but this is the good kind of wrong — it is specific enough to be checked.

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u/hydration_hank1 point·1 year ago

state the method: column, gradient, detection wavelength, injection volume

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u/aksel_palacios1 point·1 year ago

related substances are where the story lives, not the main peak

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u/yara_boateng1 point·1 year ago

Sceptical. If this were true we would see it reflected in the data and we do not.

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u/vikram_asante1 point·1 year ago

axis labels included, always

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u/micro_bump_mick1 point·1 year ago

area% and mass% are not the same and this whole post conflates them

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u/reverse_image_ron1 point·1 year ago

What was the column and what gradient?

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u/rasmus_petrescu1 point·1 year ago

Not to be pedantic but LC-MS and purity are being used interchangeably and they are not interchangeable in real life.

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u/hana_lehtinen1 point·1 year ago

instrument quality is less important than analyst consistency

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u/hplc_hobbyistruns their own column-45 points·1 year ago

co-elution is real and integration is usually not enough to resolve it

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u/fatima_yildiz1 point·1 year ago

This is the correct method framing. Column and gradient are load-bearing fields.

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u/mateusz_mensah1 point·1 year ago

area% and mass% are not the same and this whole post conflates them

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