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c/hplc·submitted 10 months ago by u/two_mil_or_one

small win: chromatogram stopped being a problem at week 95

Discussionbranch of 7 comments

Right, the HPLC question again, but with numbers this time. I have 15 data points over 40 weeks. The pattern is consistent enough that I do not think it is chance, and boring enough that nobody is going to screenshot it, which is usually a good sign. The thing I would flag for anyone new: the effect I am describing…

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7 comments, started 10 months ago
u/careful_gradient109 points·10 months ago·edited

a round-robin on baseline integration would be genuinely useful

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u/arne_nyberg35 points·10 months ago·edited

What was the column and what gradient?

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u/adaeze_batista69 points·10 months ago

area% and mass% are not the same and this whole post conflates them

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u/two_mil_or_oneOP62 points·10 months ago

A shoulder on the main peak that 3 analysts integrated 26 different ways. Same trace, 99.0 spread.

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u/vikram_asante93 points·10 months ago

axis labels included, always

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u/cormac_roos24 points·10 months ago

state the method: column, gradient, detection wavelength, injection volume

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u/matias_salgado29 points·10 months ago

Strongly agree. Largest single impurity tells a different story than total purity.

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