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

[Discussion] we are measuring LC-MS at the wrong time and calling it noise

Discussionbranch of 6 comments

I have had 23 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 12 days on nominally the same lane, which matters more in summer than in February. The independent number came back 96.8% against a claimed…

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6 comments, started 1 year ago
u/sig_figs_samMOD19 points·1 year ago

This is an urgent-care question wearing a forum question's clothes. Please contact a clinician rather than waiting for replies.

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u/peak_area_peteanalytical12 points·1 year ago

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

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u/medutest_melOP9 points·1 year 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/reverse_image_ron5 points·1 year ago

the gradient is doing the separation work, not the column alone

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u/elodie_grimaldi15 points·1 year 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/hana_lehtinen-24 points·1 year ago

instrument quality is less important than analyst consistency

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