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c/hplc·submitted 3 months ago by u/rania_okonkwo

what would you tell week-1 you about LC-MS

Labbranch of 19 comments

Right, the purity question again, but with numbers this time. I have 5 data points over 10 weeks. The pattern is consistent enough that I do not think it is chance, and boring enough that nobody is going to screenshot it, which is usually a good sign. The thing I would flag for anyone new: the effect I am describing…

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19 comments, started 3 months ago
u/zeynep_zielinski255 points·3 months ago

Crossposting this to c/glp1eu because the people who need it are not reading this community.

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u/sig_figs_sammod · analytical154 points·3 months ago

Small correction: the trial was 16 weeks, not 30. Does not change your point but people will quote it.

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[removed]114 points·3 months ago

[removed by moderator]

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u/two_mil_or_one0 points·3 months ago

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

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u/rania_okonkwoOP189 points·3 months ago

Detection wavelength? gradient and that changes at different wavelengths.

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u/rania_okonkwoOP133 points·3 months ago

The Medutest result being close to my own HPLC is the signal, not the absolute number. Both are right.

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u/peak_area_peteanalytical62 points·3 months ago

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

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u/elodie_grimaldi40 points·3 months ago·edited

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

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u/erez_yilmaz20 points·3 months ago

a round-robin on baseline integration would be genuinely useful

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u/naomi_antonsen199 points·3 months ago

Detection wavelength? HPLC and that changes at different wavelengths.

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u/mateusz_mensah54 points·3 months ago

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

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u/rasmus_kimani19 points·3 months ago

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

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