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Single comment threadYou are looking at one branch of genuine question about HPLC that I am slightly embarrassed to ask — 46 comments in the full submission. View in context.
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c/hplc·submitted 1 year ago by u/bilal_adebayo

genuine question about HPLC that I am slightly embarrassed to ask

Discussionbranch of 11 comments

Question in the title, detail here: genuine question about HPLC that I am slightly embarrassed to ask. MKM sent me the column, the gradient and the theoretical mass without being asked. That is a short list and they are on it. Started reporting my own integrations with the baseline choice stated. Arguments in my…

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11 comments, started 1 year ago
u/camila_lindqvist505 points·1 year ago

Area percent is the integrated area of your peak over the total integrated area at one wavelength on one gradient. Change any of those and the number changes without the sample changing.

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u/rasmus_kimani171 points·1 year ago·edited

Yes. Retention time is a hypothesis about identity. Mass is the answer.

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u/bilal_adebayoOP96 points·1 year ago

system suitability before you believe any number on the run

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u/samir_falk73 points·1 year ago

you cannot report to two decimals off that baseline

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u/medutest_mel47 points·1 year ago

reproducibility beats resolution if you only get one of them

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[removed]71 points·1 year ago

[removed by moderator]

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u/valeria_cardoso37 points·1 year ago

a blank injection between samples costs four minutes and settles most arguments

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u/endotoxin_elliemicro275 points·1 year ago

Agreed, and it is why CPC printing the column and gradient on the certificate is genuinely useful rather than decorative.

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u/honest_syringe_pls185 points·1 year ago

Agreed. Two analysts, one trace, two integration choices, and a spread that has nothing to do with the vial.

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u/dilara_nyberg176 points·1 year ago

That figure cannot be quoted to two decimals off that baseline. The precision is not in the data.

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u/crosspost_bot_no114 points·1 year ago

Disagree. Inter-lab spread of a point or two on this assay is ordinary and calling it a discrepancy misleads people.

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