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

[Discussion] LC-MS is doing more work than we give it credit for

Discussionbranch of 8 comments

I have had 6 orders now and I keep a table, so here is the honest summary rather than a vibe. Material has been consistent. Communication has not. Shipping has varied by about 24 days on nominally the same lane, which matters more in summer than in February. The independent number came back 98.4% against a claimed…

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8 comments, started 1 year ago
u/reverse_image_ron89 points·1 year ago

A shoulder on the main peak that 17 analysts integrated 11 different ways. Same trace, 97.2 spread.

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u/yara_boateng54 points·1 year ago·edited

A shoulder on the main peak that 17 analysts integrated 11 different ways.

Counter-anecdote: opposite result, same dose. Which mostly tells us the variance is huge.

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u/medutest_mel36 points·1 year ago

axis labels included, always

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u/nabila_espinozaOP14 points·1 year ago

The related substances profile is way more interesting than the main peak %. A 98% with 14 peaks is different from a 98% that is one 24% impurity.

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u/lina_novak130 points·1 year ago

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

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u/honest_syringe_pls66 points·1 year ago

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

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u/priya_ogunleye17 points·1 year ago

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

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