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c/hplc·submitted 5 months ago by u/dilara_nyberg

[Results] 17 weeks, 10kg, and LC-MS was the hard part

Questionbranch of 7 comments

Confession thread, sort of. I went from 2.4mg to 0.5mg much faster than I should have because the scale had stalled and I got impatient. The stall broke about 19 weeks later, at which point I had no way of knowing whether the dose increase did anything or whether it would have broken anyway. So now I have reflux I…

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7 comments, started 5 months ago
u/week_four_wall133 points·5 months ago

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

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u/dilara_nybergOP156 points·5 months ago

Ran the same vial on two columns, different purity, both right, different separation. Method matters more than equipment.

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u/erez_yilmaz47 points·5 months ago

No. This is the kind of confident post that gets copied into a screenshot and repeated for years. Where is the evidence.

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u/nnt_nate128 points·5 months ago·edited

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

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u/rina_bergstrom176 points·5 months ago

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

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u/enzo_petrescu46 points·5 months ago

axis labels included, always

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u/priya_ogunleye89 points·5 months ago

Dead space in the needle hub holds a small but non-trivial volume. On low-volume draws that can be several units.

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