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c/hplc·submitted 2 months ago by u/baseline_drifter

the method development thing finally clicked for me and I want to write it down

Methodbranch of 6 comments

the method development thing finally clicked for me and I want to write it down. Change my mind, genuinely — I have no stake in being right about this. Mass spectrometry answers identity. UV purity answers relative quantity under the run conditions. A document with one and not the other is answering half the…

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6 comments, started 1 months ago
u/niels_lindqvist139 points·1 months ago·edited

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/reverse_image_ron46 points·1 months ago

Ran a blank after a high-concentration injection and found the carryover I had been calling an impurity.

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u/mass_spec_maggieMS17 points·1 months ago

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

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u/aksel_kjaer12 points·1 months ago

axis labels or the trace is decoration

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u/amara_haddad5 points·1 months ago

report the method or do not report the number

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u/step_count_stan108 points·1 months ago

Carryover from a previous high-concentration injection looks exactly like a small impurity. The blank injection is four minutes and it removes the ambiguity entirely.

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