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c/hplc·submitted 1 months ago by u/canada_coverage

someone explain LC-MS to me like I have not read a paper in years

Methodbranch of 5 comments

Posting this because I searched for it and got nothing useful. Setup: 0.5mg, week 62, constipation present but not ruining anything. I changed exactly one variable — gradient — and tracked it for 15 weeks. Result: a difference, but a small one, and well inside what I would call noise if someone else posted it. So I…

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5 comments, started 1 months ago
u/hazard_ratio_halstats-19 points·1 months ago

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

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u/matias_salgado1 point·1 months ago

A shoulder on the main peak that 21 analysts integrated 12 different ways. Same trace, 97.4 spread.

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u/canada_coverageOP-27 points·1 months ago

The related substances profile is way more interesting than the main peak %. A 98% with 15 peaks is different from a 98% that is one 22% impurity.

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u/cormac_roos1 point·1 months ago

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

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u/arne_nyberg1 point·1 months ago·edited

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

Adding to this: integration is doing more work than the comment implies.

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