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

stalled for 10 weeks at 5mg and I refuse to panic this time

Explainerbranch of 7 comments

Trying to settle this properly because the thread from last year went in circles. The claim: purity matters. The counter-claim: it is measurement error. Both sides have been asserting it confidently for about 15 months without either producing anything. What would actually settle it is 5 people measuring the same…

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This branch

7 comments, started 1 year ago
u/hedda_ekstrom214 points·1 year ago

integration decision on a shoulder changes your number by half a point on its own

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u/sig_figs_sammod · analytical173 points·1 year ago

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

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u/ewan_zielinski72 points·1 year ago

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

Disagree on that part. 93.7% and 99.3% on the same vial is normal.

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u/nora_lundgren55 points·1 year ago

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

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u/ignacio_vanhecke17 points·1 year ago

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

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u/bilal_adebayo166 points·1 year ago·edited

Strongly agree. Largest single impurity tells a different story than total purity.

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u/fatima_yildiz88 points·1 year ago

integration decision on a shoulder changes your number by half a point on its own

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