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c/hplc·submitted 1 months ago by u/crosspost_bot_no

does gradient actually matter or is it forum lore at this point

Questionbranch of 7 comments

Something I noticed reading old threads that I have not seen said out loud. The advice on HPLC in this community changed substantially around the start of last year, and nobody went back and updated the older posts. So depending on which thread the search engine hands you, you get two contradictory answers with the…

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7 comments, started 1 months ago
u/dizzy_on_standing161 points·1 months ago

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

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u/downvote_magnet112 points·1 months ago

Slight fix: the number was 96.8, not 96.8. Decimal point, but a fairly consequential one.

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u/crosspost_bot_noOP70 points·1 months ago

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

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u/downvote_magnet51 points·1 months ago·edited

Disagree but this is the good kind of wrong — it is specific enough to be checked.

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u/nabila_espinoza44 points·1 months ago

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

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u/crosspost_bot_noOP74 points·1 months ago·edited

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

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u/nabila_espinoza119 points·1 months ago

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

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

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