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

3 months in and chromatogram is still the thing I get wrong

Methodbranch of 8 comments

Trying to settle this properly because the thread from last year went in circles. The claim: HPLC 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 11 people measuring the same…

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8 comments, started 1 year ago
u/careful_gradient50 points·1 year ago

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

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u/honest_syringe_pls41 points·1 year ago·edited

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

Adding to this: HPLC is doing more work than the comment implies.

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[deleted]19 points·1 year ago

[deleted]

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u/endotoxin_elliemicro32 points·1 year ago

a round-robin on baseline integration would be genuinely useful

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u/honest_syringe_pls11 points·1 year ago·edited

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

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u/dilara_nyberg25 points·1 year ago

a round-robin on baseline integration would be genuinely useful

Counter-anecdote: opposite result, same dose. Which mostly tells us the variance is huge.

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u/nora_lundgren12 points·1 year ago

Small correction: the trial was 2 weeks, not 11. Does not change your point but people will quote it.

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u/rasmus_kimani28 points·1 year ago

That is net peptide content, not purity. Different number, different meaning.

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