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c/hplc·submitted 2 months ago by u/ewan_tulloch

[Lab] SGN cagri — VendorInvestigate came back 93.7% against a claimed 98.6%

Labbranch of 9 comments

Confession thread, sort of. I went from 0.25mg to 10mg much faster than I should have because the scale had stalled and I got impatient. The stall broke about 22 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…

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9 comments, started 2 months ago
u/alcohol_aversion440 points·2 months ago

instrument quality is less important than analyst consistency

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u/peak_area_peteMOD271 points·2 months ago

Retitled to remove editorialising. Put the evidence in the body.

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[removed]175 points·2 months ago

[removed by moderator]

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u/ewan_tullochOP198 points·2 months ago

A shoulder on the main peak that 18 analysts integrated 25 different ways. Same trace, 99.3 spread.

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u/ewan_tullochOP88 points·2 months ago

axis labels included, always

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u/egfr_watcher637 points·2 months ago

a round-robin on baseline integration would be genuinely useful

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u/careful_gradient277 points·2 months ago·edited

Yeah, the chromatogram profile matters more than the headline number.

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u/rina_bergstrom435 points·2 months ago

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

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u/matias_salgado210 points·2 months ago

Yeah, the chromatogram profile matters more than the headline number.

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