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c/hplc·submitted 5 months ago by u/liv_okafor

genuine question about chromatogram that I am slightly embarrassed to ask

Questionbranch of 7 comments

Genuine question, and the title is the question: genuine question about chromatogram that I am slightly embarrassed to ask. Sent the same vial to PeptideMeter and Medutest. 98.8% against a claimed 98.0%. The difference was the gradient, not the material. System suitability — repeat injections, tailing factor, plate…

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7 comments, started 5 months ago
u/kofi_ferreira192 points·5 months ago

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 question, and the half it answers should be stated.

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u/sig_figs_samMOD96 points·5 months ago

Retitled: the original claimed a comparison the post does not actually make.

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u/ewan_tulloch131 points·5 months ago

Bought a second-hand instrument and learned more in six months of fixing it than in three years of reading traces.

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[deleted]85 points·5 months ago

[deleted]

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u/hugo_bergstrom48 points·5 months ago

report the method or do not report the number

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u/nabila_espinoza64 points·5 months 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/dead_space_doug130 points·5 months ago

Do you have the mass, or only the UV trace?

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