#hplc-massspec 2025-10-09

Thursday14 messages3 participantstimes are UTC

Highlights from this day

endotoxin_ed — ok so do you trust an area percent from a shallow gradient 14:22
endotoxin_ed — is there any point running a blank if the sample is the question 15:56
endotoxin_ed — a warm transit can put a visible degradant peak on a chromatogram. that is what 19 days at ambient does 16:01

ok so do you trust an area percent from a shallow gradient

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how would a truncation sequence show up

run a blank

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the first peak is the solvent. it is always the solvent

coming back after 16 months, what changed in how you read these

plus 0.98 is deamidation

quick one is uv at 214 or 280 better for peptides

ask for the trace

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how do you tell co-elution from a clean single peak

update on the earlier thing baseline is drifting badly, is that the column or the mobile phase

is there any point running a blank if the sample is the question

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if somebody says they ran a mass spec and does not show you a spectrum, that is a claim, not a result

a warm transit can put a visible degradant peak on a chromatogram. that is what 19 days at ambient does

integration choices move the number by a few tenths easily. that is most of your inter-lab variance