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

genuine question about purity that I am slightly embarrassed to ask

Questionbranch of 6 comments

Question in the title, detail here: genuine question about purity that I am slightly embarrassed to ask. WWB 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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6 comments, started 1 months ago
u/cagrilintide_enthusiast17 points·1 months ago

Did you run a blank between injections?

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u/crosspost_bot_noOP10 points·1 months ago

report the method or do not report the number

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u/honest_syringe_pls6 points·1 months ago

Same method at both labs, or two different gradients?

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u/endotoxin_elliemicro2 points·1 months ago

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

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u/crosspost_bot_no12 points·1 months ago

system suitability before you believe any number on the run

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u/niels_lindqvist3 points·1 months ago

Sent the same vial to PeptideMeter and VendorInvestigate. 99.3% against a claimed 98.5%. The difference was the gradient, not the material.

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